Make benchmark configuration files consistent

[msulprizio]

• Fixed comments so they are consistent in gcpy/benchmark/config/*.yml
• Changed default gchp resolution to c24
• Set gchp switch is_pre_14.0: False by default

[msulprizio]

1. Also update comments etc. in the benchmark/cloud/template*.yml files accordingly
2. Also include a changelog update.

Thanks @yantosca. These should now be addressed in https://github.com/geoschem/gcpy/pull/264/commits/502ffaf679ad7913e86aa2418de57dcf0c1fd378.