Bug 1858079

Description of problem:

This issue was uncovered while investigating a potential customer issue in a different ticket:

https://bugzilla.redhat.com/show_bug.cgi?id=1846621

It is possible to get into a stuck state if:

1. A playbook is trying to be run with Escalate privileges checked
2. The credential record attached to the playbook doesn't have a `become_password` set (is `nil`)

Version-Release number of selected component (if applicable): 5.11.0


How reproducible:  Always (given the above conditions)


Steps to Reproduce:
1. Enable EmbeddedAnsible
2. Include a plabook repo
3. Create a new machine credential that doesn't have a become password
4. Ensure said become_password is `nil` (instructions for doing this below)
5. Create a Ansible Playbook service that checks `Esclate Privileges`
6. Run said playbook service


Actual results:

The `ansible-runner` process hangs with last line of output being "BECOME Password:", similar to what is below

    ansible-playbook 2.9.9
      config file = /root/.ansible.cfg
      configured module search path = ['/root/.ansible/plugins/modules', '/usr/share/ansible/plugins/modules']
      ansible python module location = /usr/lib/python3.6/site-packages/ansible
      executable location = /usr/bin/ansible-playbook
      python version = 3.6.8 (default, Dec  5 2019, 15:45:45) [GCC 8.3.1 20191121 (Red Hat 8.3.1-5)]
    Using /root/.ansible.cfg as config file
    BECOME password: 


Expected results:

Runs successfully without timing out.


Additional info:

1. Already fixed with https://github.com/ManageIQ/manageiq/pull/20282

2. To view the output without waiting for the process to fully timeout, after about 5 minutes have passed from ordering the playbook, you can run the following:

    $ sudo cat /tmp/ansible-runner202000101-1234-7890abc/artifacts/result/stdout

The above is a uniq tmp dir that is generated, so the exact directory might be different then what is on your system.  If only running one playbook service at a time, this should be the only directory with this structure.

3. To ensure that the machine credential is `nil`, you can run the following in a terminal for testing the fail case, you can run the following in a console

        $ vmdb
        $ bin/rails c
        irb> ManageIQ::Providers::EmbeddedAnsible::AutomationManager::MachineCredential.where(:name => "s-cfme-ansible").first.update(:become_password => nil)