How to install pulp-admin on RHEL7/ foreman-2.4 / Katello 4.0.0

[laimsi]

I oppened dedicated topic for Pulp3 and tasks stuck issue:
Tasks stuck with “waiting for Pulp to start the task” - foreman-2.4 / Katello 4.0.0 / Pulp3 - Support - TheForeman