Supported versions configmap should be removed

[SrishT]

Description

The operator currently validates the version of the pravega image before installation, and also checks the version before allowing upgrade or rollback, using the validating webhook. While we still want to only allow rollback to the last stable version before the upgrade failed, we want to remove the version validation which is currently done before any installation or upgrade, and hence maintaining the supported versions configmap should no longer be necessary.

Importance

nice to have

Location

charts/pravega-operator/templates/version_map.yaml
deploy/version_map.yaml