Support multi-arch worker nodes on ROSA for Keycloak deployments

[kami619]

Description

• When creating a Keycloak in Keycloak Benchmark in a mixed ARM and non-ARM cluster, Keycloak and the Keycloak Operator should deploy on ARM nodes.

Discussion

https://github.com/keycloak/keycloak/issues/34442

Motivation

No response

Details

• This comment would be helpful in refactoring the BuildConfig used for building Keycloak custom images with AWS JDBC driver support for AuroraDB. https://github.com/keycloak/keycloak-benchmark/issues/1022#issuecomment-2451901843
• We need take care of https://github.com/keycloak/keycloak-benchmark/pull/1025#issuecomment-2451959353, as this would be forcing ARM deployments by default and needs to be controlled by a new CPU_ARCH variable or something similar.

[ahus1]

As discussed, we won't run multi-arch support in our nightly tests, so we skip implementing this now.

The current snippet should be removed:

 scheduling:
    affinity:
      nodeAffinity:
        requiredDuringSchedulingIgnoredDuringExecution:
          nodeSelectorTerms:
            - matchExpressions:
                - key: kubernetes.io/arch
                  operator: In
                  values:
                    - arm64
...

If we need to do it in the future, we might use this as a how-to guide: https://developers.redhat.com/articles/2024/08/27/building-multi-architecture-container-images-openshift-container-platform