Thank you for your help @jjeffers and @Justin_Sherrill.
I can confirm that /etc/puppetlabs/code/environments is writable by apache:
[centos@foreman ~]$ ls -la /etc/puppetlabs/code/environments
total 0
drwxr-xr-x. 4 apache root 36 04-17 00:14 .
drwxr-xr-x. 4 root root 39 04-16 23:58 ..
drwxr-xr-x. 2 apache root 6 04-17 00:14 common
drwxr-xr-x. 5 root root 87 04-16 23:58 production
Also, don’t see any errors in /var/log/messeges (one thing I can see is 404 HTTP response code for /puppet/environments/KT_Default_Organization_dev_GitContentView_2/classes):
Logs
Apr 28 01:40:00 foreman pulp: celery.worker.strategy:INFO: Received task: pulp.server.async.tasks._queue_reserved_task[61bb6821-22d8-4867-8c39-7f6bd766fc87]
Apr 28 01:40:00 foreman pulp: celery.worker.strategy:INFO: Received task: pulp.server.managers.repo.unit_association.associate_from_repo[df04bd22-1a54-4b67-8545-211ffe6cf857]
Apr 28 01:40:00 foreman pulp: celery.worker.strategy:INFO: Received task: pulp.server.async.tasks._release_resource[02901e3a-53bb-4bc7-967d-2049866a20ff]
Apr 28 01:40:00 foreman pulp: celery.app.trace:INFO: [61bb6821] Task pulp.server.async.tasks._queue_reserved_task[61bb6821-22d8-4867-8c39-7f6bd766fc87] succeeded in 0.02925956s: None
Apr 28 01:40:00 foreman pulp: celery.app.trace:INFO: [df04bd22] Task pulp.server.managers.repo.unit_association.associate_from_repo[df04bd22-1a54-4b67-8545-211ffe6cf857] succeeded in 0.0283528470001s: {'units_successful': [{'unit_key': {...}, 'type_id': 'puppet_module'}, {'unit_key': {...}, 'type_id': 'puppet_module'}]}
Apr 28 01:40:00 foreman pulp: celery.app.trace:INFO: [02901e3a] Task pulp.server.async.tasks._release_resource[02901e3a-53bb-4bc7-967d-2049866a20ff] succeeded in 0.00126901099998s: None
Apr 28 01:40:00 foreman pulp: celery.worker.strategy:INFO: Received task: pulp.server.async.tasks._queue_reserved_task[05318aa9-9c25-4d7a-956a-e15244d04f31]
Apr 28 01:40:00 foreman pulp: celery.worker.strategy:INFO: Received task: pulp.server.managers.repo.publish.publish[dc4d0d29-21c2-4934-a5e5-b6d8a96e6e73]
Apr 28 01:40:00 foreman pulp: celery.app.trace:INFO: [05318aa9] Task pulp.server.async.tasks._queue_reserved_task[05318aa9-9c25-4d7a-956a-e15244d04f31] succeeded in 0.01779762s: None
Apr 28 01:40:00 foreman pulp: celery.worker.strategy:INFO: Received task: pulp.server.async.tasks._release_resource[2299270e-e69d-43af-b76a-1f0de1717a80]
Apr 28 01:40:00 foreman pulp: pulp_puppet.plugins.distributors.publish:INFO: [dc4d0d29] Beginning publish for repository <1-GitContentView-dev-puppet-47668efd-abe3-4498-8d90-09e82f127adb>
Apr 28 01:40:00 foreman pulp: pulp_puppet.plugins.distributors.publish:INFO: [dc4d0d29] Initializing build directory for repository <1-GitContentView-dev-puppet-47668efd-abe3-4498-8d90-09e82f127adb>
Apr 28 01:40:00 foreman pulp: celery.worker.strategy:INFO: Received task: pulp.server.async.tasks._queue_reserved_task[eaa77a7e-6985-4f15-a4b7-7faa1c8cd36a]
Apr 28 01:40:00 foreman pulp: pulp_puppet.plugins.distributors.publish:INFO: [dc4d0d29] Creating symlinks for modules in repository <1-GitContentView-dev-puppet-47668efd-abe3-4498-8d90-09e82f127adb>
Apr 28 01:40:00 foreman pulp: pulp_puppet.plugins.distributors.publish:INFO: [dc4d0d29] Generating metadata for repository <1-GitContentView-dev-puppet-47668efd-abe3-4498-8d90-09e82f127adb>
Apr 28 01:40:00 foreman pulp: celery.worker.strategy:INFO: Received task: pulp.server.managers.repo.publish.publish[f62c4f9c-ccae-4b1b-94b3-7b7275bf3619]
Apr 28 01:40:00 foreman pulp: pulp_puppet.plugins.distributors.publish:INFO: [dc4d0d29] Making newly built repository live for repository <1-GitContentView-dev-puppet-47668efd-abe3-4498-8d90-09e82f127adb>
Apr 28 01:40:00 foreman pulp: celery.worker.strategy:INFO: Received task: pulp.server.async.tasks._release_resource[d12432d1-0ebb-453c-af5a-f1a0c41ef988]
Apr 28 01:40:00 foreman pulp: celery.app.trace:INFO: [eaa77a7e] Task pulp.server.async.tasks._queue_reserved_task[eaa77a7e-6985-4f15-a4b7-7faa1c8cd36a] succeeded in 0.024446841s: None
Apr 28 01:40:00 foreman pulp: pulp_puppet.plugins.distributors.publish:INFO: [dc4d0d29] Cleaning up build directory for repository <1-GitContentView-dev-puppet-47668efd-abe3-4498-8d90-09e82f127adb>
Apr 28 01:40:00 foreman pulp: celery.app.trace:INFO: [dc4d0d29] Task pulp.server.managers.repo.publish.publish[dc4d0d29-21c2-4934-a5e5-b6d8a96e6e73] succeeded in 0.0568741679999s: {'exception': None, 'repo_id': '1-GitContentView-dev-puppet-47668efd-abe3-4498-8d90-09e82f127adb', 'traceback': None, 'started': '2020-04-28T05:40:00Z', '_ns': 'repo_publish_results', 'completed': datetime.datetime(2020, 4, 28, 5, 40, 0, 915237, tzinfo=<isodate.tzinfo.Utc object at 0x7f3ce3fd1f50>), 'error_message': None, 'distributor_type_id': 'puppet_distributor', 'distributor_id': '1-GitContentView-dev-puppet-47668efd-abe3-4498-8d90-09e82f127adb_puppet', 'summary': {'total_execution_time': 0}, 'result': 'success', 'id': '5ea7c1b047917e09e34827bb', 'details': {}}
Apr 28 01:40:00 foreman pulp: celery.app.trace:INFO: [2299270e] Task pulp.server.async.tasks._release_resource[2299270e-e69d-43af-b76a-1f0de1717a80] succeeded in 0.00338046100001s: None
Apr 28 01:40:01 foreman pulp: celery.app.trace:INFO: [f62c4f9c] Task pulp.server.managers.repo.publish.publish[f62c4f9c-ccae-4b1b-94b3-7b7275bf3619] succeeded in 0.098415339s: {'exception': None, 'repo_id': '1-GitContentView-dev-puppet-47668efd-abe3-4498-8d90-09e82f127adb', 'traceback': None, 'started': '2020-04-28T05:40:00Z', '_ns': 'repo_publish_results', 'completed': datetime.datetime(2020, 4, 28, 5, 40, 1, 38702, tzinfo=<isodate.tzinfo.Utc object at 0x7f3ce3fd1f50>), 'error_message': None, 'distributor_type_id': 'puppet_install_distributor', 'distributor_id': '1-GitContentView-dev-puppet-47668efd-abe3-4498-8d90-09e82f127adb', 'summary': 'success', 'result': 'success', 'id': '5ea7c1b147917e09e34827bc', 'details': {'errors': [], 'success_unit_keys': [{...}, {...}]}}
Apr 28 01:40:01 foreman pulp: celery.app.trace:INFO: [d12432d1] Task pulp.server.async.tasks._release_resource[d12432d1-0ebb-453c-af5a-f1a0c41ef988] succeeded in 0.00126588900002s: None
Apr 28 01:40:01 foreman smart-proxy: foreman.company.com - - [28/Apr/2020:01:40:01 EDT] "GET /puppet/environments/KT_Default_Organization_dev_GitContentView_2/classes HTTP/1.1" 404 73
Apr 28 01:40:01 foreman smart-proxy: - -> /puppet/environments/KT_Default_Organization_dev_GitContentView_2/classes
Apr 28 01:40:01 foreman smart-proxy: foreman.company.com - - [28/Apr/2020:01:40:01 EDT] "GET /puppet/environments HTTP/1.1" 200 23
Apr 28 01:40:01 foreman smart-proxy: - -> /puppet/environments
Apr 28 01:40:02 foreman smart-proxy: foreman.company.com - - [28/Apr/2020:01:40:01 EDT] "GET /puppet/environments HTTP/1.1" 200 23
Apr 28 01:40:02 foreman smart-proxy: - -> /puppet/environments
Apr 28 01:40:02 foreman smart-proxy: foreman.company.com - - [28/Apr/2020:01:40:02 EDT] "GET /puppet/environments HTTP/1.1" 200 23
Apr 28 01:40:02 foreman smart-proxy: - -> /puppet/environments