Stop building che-postgres image since it's not used in the Che operator CSV

[nickboldt]

Is your task related to a problem? Please describe

In the che operator CSV...

• https://github.com/eclipse-che/che-operator/blob/main/bundle/next/eclipse-che-preview-openshift/manifests/che-operator.clusterserviceversion.yaml#L976-L979
• https://github.com/eclipse-che/che-operator/blob/main/bundle/stable/eclipse-che-preview-openshift/manifests/che-operator.clusterserviceversion.yaml#L976-L979

... we no longer reference the che-postgres images:

• https://quay.io/repository/eclipse/che-postgres?tab=tags
• https://github.com/eclipse-che/che-server/tree/main/dockerfiles/postgres
  ** https://github.com/eclipse-che/che-server/blob/main/dockerfiles/postgres/Dockerfile#L9 (last updated 4 years ago, uses postgres 9.6)

And quay.io/eclipse/che-postgres:next includes:

$➔ podman run -it --rm --entrypoint /bin/bash quay.io/eclipse/che-postgres:next -c "/usr/bin/postgres --version"
podman run -it --rm --entrypoint /bin/bash
postgres (PostgreSQL) 9.6.10

Describe the solution you'd like

• Stop building che-postgres image as part of CI and release builds
• update docs Che docs page about PostgreSQL has outdated links #21348

Describe alternatives you've considered

No response

Additional context

No response

[nickboldt]

From Anatolii, sounds like this is a non-starter, but if we decide to drop Helm entirely we could review:

Since installation with Helm is not equal to installation with operator some images are different.
Here is the Dockerfile [1] Besides PostgreSQL 9.6 image, it contains some configuration that is required only for Helm
So, simple replacement won't work. My suggestions are:

Don't touch anything related to Helm here. Basically these charts are outdated, but maybe someone from community uses them
or
Completely remove everything related to HelmCharts
[1] https://github.com/eclipse-che/che-server/blob/main/dockerfiles/postgres/Dockerfile