Type check glcollate/pipeline.py

Make CollatePipeline._job_selection a typing overloaded function. If action is None then it returns a dict[str, CollateJob] but if the action was passed then it returns dict[str, dict[int, Any]]. Bypass executor if action is not passed as it is a simple dictionary creation.

Make CollatePipeline__query_dictionary_keys a generic function as it accepts any dictionary type and then flattens it.

Depends on !78 (merged) & !79 (merged)