SelectWorkspaceClass in ProjectSettings should not depend on PVC feature flag

[jldec]

The new workspace class selector is not visible in any project settings on gitpod.io
It appears that the selector depends on the PVC feature flag.

https://github.com/gitpod-io/gitpod/blob/main/components/dashboard/src/projects/ProjectSettings.tsx#L162-L164

This feature has been requested in connection with this customer support issue (internal)

cc: @svenefftinge @atduarte

[jldec]

Related to #14535

[kylos101]

@jldec I removed from the Team Workspace inbox. Let us know if anything is needed in a new issue?