[minor] Add Job to optionally configure MAS welcome message on install

[tomklapiscak]

Description

Setting welcome_message in ibm-mas-suite.yaml like so:

ibm_mas_suite:
  ...
  welcome_message: "Hello World!"

will prompt ArgoCD to run a Job after the Suite is installed to update the Welcome message shown on the MAS Login screen, e.g.:

Note:

• This feature depends on a new internal API that will be only available in MAS 9.1.7 or later. Attempting to set this configuration against an earlier version of MAS will result in the Job being stuck in a Failed state and so will prevent ArgoCD sync from progressing past the Suite
• The welcome message will only be updated (a) the first time the Job has run or (b) if the welcome_message set in ibm-mas-suite.yaml is changed. If the customer subsequently overrides the welcome message via the MAS UI/API, the Job will not attempt to revert their change; this is intentional

Related Issues

https://jsw.ibm.com/browse/MASCORE-10796

Testing

• Verified that the suite chart still renders when no welcome_message field is set

• Verified that the Job sets the welcome message when it runs for the first time after the suite has finished installing, job logs:

MAS Welcome Message Setup
===============================

This Job will ensure that the MAS welcome message (i.e. that shown at the bottom of the login screen)
is set to the value defined in gitops configuration.
The welcome message will only be updated if one of the following are true:
 - This Job has never been run before (i.e. after the Suite is installed for the first time)
 - The welcome message defined in the gitops configuration has changed since the last time this Job ran
If the welcome message is changed via the MAS UI/API, this Job will NOT revert the change - this is intentional.

Fetch Welcome Message last set by this Job from ConfigMap set-welcome-message-state
------------------------------------------------
Error from server (NotFound): configmaps "set-welcome-message-state" not found
ConfigMap set-welcome-message-state was not found, Job has never been run, so proceed ...

Setting MAS Welcome Message
---------------------------
  % Total    % Received % Xferd  Average Speed   Time    Time     Time  Current
                                 Dload  Upload   Total   Spent    Left  Speed

  0     0    0     0    0     0      0      0 --:--:-- --:--:-- --:--:--     0
100  1030  100   515  100   515   6058   6058 --:--:-- --:--:-- --:--:-- 12117
{"message":"Hello world"}

Result
---------------------------
Successfully set welcome message

Updating ConfigMap set-welcome-message-state
---------------------------
configmap/set-welcome-message-state created

• Verified that the Job does not attempt to update the welcome message if it is rerun without any changes to the welcome message in the Gitops config, job logs:

MAS Welcome Message Setup
===============================

This Job will ensure that the MAS welcome message (i.e. that shown at the bottom of the login screen)
is set to the value defined in gitops configuration.
The welcome message will only be updated if one of the following are true:
 - This Job has never been run before (i.e. after the Suite is installed for the first time)
 - The welcome message defined in the gitops configuration has changed since the last time this Job ran
If the welcome message is changed via the MAS UI/API, this Job will NOT revert the change - this is intentional.

Fetch Welcome Message last set by this Job from ConfigMap set-welcome-message-state
------------------------------------------------
Gitops configuration and the welcome message last applied by this Job are the same, so abort ...

• Verified that the Job will update the welcome message if the welcome message in gitops config is changed, job logs:

MAS Welcome Message Setup
===============================

This Job will ensure that the MAS welcome message (i.e. that shown at the bottom of the login screen)
is set to the value defined in gitops configuration.
The welcome message will only be updated if one of the following are true:
 - This Job has never been run before (i.e. after the Suite is installed for the first time)
 - The welcome message defined in the gitops configuration has changed since the last time this Job ran
If the welcome message is changed via the MAS UI/API, this Job will NOT revert the change - this is intentional.

Fetch Welcome Message last set by this Job from ConfigMap set-welcome-message-state
------------------------------------------------
Gitops configuration contains a different welcome message than that last applied by this Job, so proceed ...

Setting MAS Welcome Message
---------------------------
  % Total    % Received % Xferd  Average Speed   Time    Time     Time  Current
                                 Dload  Upload   Total   Spent    Left  Speed

  0     0    0     0    0     0      0      0 --:--:-- --:--:-- --:--:--     0
100  1052  100   526  100   526   6045   6045 --:--:-- --:--:-- --:--:-- 12232
{"message":"Goodbye World!"}

Result
---------------------------
Successfully set welcome message

Updating ConfigMap set-welcome-message-state
---------------------------
configmap/set-welcome-message-state configured