stx-openstack: App fails to apply due to non-tolerated taint in stand-by controller

[Luan Nunes Utimura]

Brief Description
-----------------

It has been observed that on Standard systems, `stx-openstack` is failing to apply due to a non-tolerated taint in the stand-by controller (node-role.kubernetes.io/master).

Severity
--------
Critical:
  * This bug prevents the app from being applied;
  * This bug affects the automated tests (sanity and regression).

Steps to Reproduce
------------------
On a Standard system, attempt to apply `stx-openstack`.

Expected Behavior
------------------
`stx-openstack` is applied successfully.

Actual Behavior
----------------
`stx-openstack` fails to apply due to a non-tolerated taint in the stand-by controller.

Reproducibility
---------------
Reproducible.

System Configuration
--------------------
Standard.

Branch/Pull Time/Commit
-----------------------
Branch `master`.

Last Pass
---------
Before [1] was merged.

Timestamp/Logs
--------------
```
Warning FailedScheduling 4m39s (x766 over 2d15h) default-scheduler 0/4 nodes are available: 1 node(s) didn't match pod anti-affinity rules, 1 node(s) had untolerated taint {node-role.kubernetes.io/master: }, 2 node(s) didn't match Pod's node affinity/selector. preemption: 0/4 nodes are available: 1 No preemption victims found for incoming pod, 3 Preemption is not helpful for scheduling.
```

Test Activity
-------------
Sanity/Regression.

Workaround
----------
Revert [1].

[1] https://review.opendev.org/c/starlingx/openstack-armada-app/+/885301