Adjust implementation to create `WorkspaceType`s without `WorkspaceAuthenticationConfigruation` reference

[aaronschweig]

Current State:

Currently the operator just blindly applies a WorkspaceType with a set reference to a WorkspaceAuthenticationConfiguration. This leaks a few assumptions we make with regards to authentication into the account-operator, even if no other component ever fulfills this promise.

We want to change that behaviour.

During WorkspaceType creation we do NOT set this reference, but rather let it set by the component that fulfills the authentication configuration

Goals

• Remove reference from WorkspaceType on creation
• Make sure an alternatice component sets this reference to not break the authentication chain