Format Github exceptions in Airflow pipeline

[kiersten-stokes]

Parses the GithubException object into its status and data properties and writes them to formatted error string, along with a message that directs the user to check their entered runtime configuration details.

Covers the following cases:

• incorrect branch name
• incorrect repository name
• incorrect repository token
• incorrect GitHub server API endpoint

Screenshots

Incorrect branch name. Error caught in upload_dag function

Incorrect repository name. Error caught in get_repo function on GithubClient init and moves up the exception chain to the try/except block in processor_airflow.py

Fixes #1332

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[kevin-bates]

This looks really good @kiersten-stokes - thank you. My only recommendation would be to update the first word in your description from "Addresses" to one of the documented keywords that trigger an issue's auto-closure from a merged PR. (Although not explicitly stated, case doesn't matter. I'm partial to "Resolves" myself. 😄 )

[kiersten-stokes]

That's a great tip, thank you @kevin-bates! I didn't know that this feature existed until now

[kevin-bates]

Just to clarify the keyword stuff, the placement doesn't matter (based on what I've read). I suspect the only aspect that matters is the relationship of the keyword to the issue number. Also, I've just learned that this keyword/auto-close stuff only applies when the PR targets the default branch (just FYI).