Derive UDWF (`WindowUDFImpl`) equality from PartialEq, Hash

[findepi]

Same as #16865 but for UDWF (WindowUDFImpl).

• depends on Derive UDF (ScalarUDFImpl) equality from PartialEq, Hash #16865. That issue needs to be done first to define how it should be done.
• this should update all WindowUDFImpl that today have explicit equals/hash implementations
  • can be located with a regex WindowUDFImpl for((?!\n\}).|\n)* *fn equals