This is a follow-up from #10098.

The current approach has several severe downsides:

• It is done by explicitly merging every field that is very error-prone and hard to validate (a field could be easily missed and/or wrongly merged).
• The test coverage is incomplete, doesn't cover all fields.

To consider this issue resolved:

• Increase test coverage to include every field.
• If possible, merge the fields in a generic way (probably by using reflections).
• Consider removing Pod-Templates completely if not required anymore.