Added ability to trust a custom bundle CA

[tchellomello]

Fixes: #376

This PR introduces the initContainer to prepare the RHEL PKI for the sub-containers used in AWX. This approach allows having the update-trust-ca executed one instead for each container via lifecycle.

See the #376 for the full testing report

Creating secret:

$ cat Toca_ROOT_CA.crt  Toca_Intermediate_CA.crt  > /tmp/bundle-ca.crt
$ kubectl create secret generic  awx-ssl-ca-custom  --from-file=bundle-ca.crt=/tmp/bundle-ca.crt

Modifying awx spec:

apiVersion: awx.ansible.com/v1beta1
kind: AWX
....
spec:
  bundle_cacert_secret: awx-ssl-ca-custom
....

Result:

(py39) mdemello@storm ~> kubectl iexec awx /bin/bash                                                                                                                                                                                     00:53:40
Namespace: default | Pod: ✔ awx-ssl-ca-6cccf6577d-jzrk9
Container: ✔ awx-ssl-ca-task
bash-4.4$ ls -la /etc/pki/ca-trust/source/anchors/bundle-ca.crt 
-rw-r--r--. 1 root root 4086 Jun 11 04:51 /etc/pki/ca-trust/source/anchors/bundle-ca.crt

[rooftopcellist]

I agree with the approach of this PR, and it works, but is using this image OK? @wenottingham @Spredzy

[wenottingham]

I would assume in other places this would be overriden. @tchellomello ?

[tchellomello]

Yes @wenottingham. The variables init_container_image and init_container_image_version can be overriden.

[rooftopcellist]

After rebasing, this looks good to me. Nice work @tchellomello !