PocketCoffea at coffea-casa AF

[oshadura]

• make sure we can execute simple examples at coffea-casa: https://pocketcoffea.readthedocs.io/en/main/analysis_example.html
• add coffea casa executor https://pocketcoffea.readthedocs.io/en/main/running.html#adding-support-for-a-new-executor-site
• make dataset builder e.g. dataset tools, to work with auth_type: oidc

[oshadura]

Adding coffea casa executor, tested at https://coffea.casa: PocketCoffea/PocketCoffea#135