Replace DeploymentConfig in openshift quickstarts to avoid warning in output

[xingxingxia]

Currently, the YAML manifests use DeploymentConfig and produce a deprecation warning:

$ oc new-project keycloak
$ oc process -n keycloak -f https://raw.githubusercontent.com/keycloak/keycloak-quickstarts/latest/openshift/keycloak.yaml ...snipped... | oc create -n keycloak -f -
service/keycloak created
route.route.openshift.io/keycloak created
Warning: apps.openshift.io/v1 DeploymentConfig is deprecated in v4.14+, unavailable in v4.10000+
deploymentconfig.apps.openshift.io/keycloak created

This PR updates to use Deployment, which doesn't produce warning now:

$ oc process -n keycloak -f https://raw.githubusercontent.com/xingxingxia/keycloak-quickstarts/refs/heads/replace-deploymentconfig-in-main/openshift/keycloak.yaml ...snipped... | oc create -n keycloak -f -
service/keycloak created
route.route.openshift.io/keycloak created
deployment.apps/keycloak created

@vmuzikar , could you help review/approve if having no objection? Thanks!

[xingxingxia]

@mposolda , could you help review / approve? Thank you!

[shawkins]

@vmuzikar I'm ok with this change.

However I'm not sure we should even be using a Deployment given we recommend against that in the scaling guide. If I understand correct it's still a longer-term goal to support parrallel StatefulSets or Deployments cc @ahus1 @mhajas

As long as it's understood this is for a single replica for now, we should be good.

[ahus1]

@shawkins - I agree to proceed with this PR.

Still I know that there are a lot of bad practices in this example. This not being StatefulSet is one thing, missing startup probe another as well as using start-dev which might make sense in local dev setups, but IMHO not when deploying to Kubernetes. It is also not using the kubernetes ping and a headless service for scaling.