[AIRFLOW-4846] Allow specification of an existing secret containing git credentials for init containers

[george-miller]

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Jira

• My PR addresses the following Airflow Jira issues and references them in the PR title. For example, "[AIRFLOW-XXX] My Airflow PR"
  • https://issues.apache.org/jira/browse/AIRFLOW-4846

Description

• Here are some details about my PR, including screenshots of any UI changes:

I would like to specify username/password git credentials as a secret so that I don't have plaintext username/passwords stored in my airflow configuration file. We can assume the given secret has GIT_USERNAME and GIT_PASSWORD fields.

Tests

• My PR adds the following unit tests OR does not need testing for this extremely good reason:

Commits

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  3. Subject does not end with a period
  4. Subject uses the imperative mood ("add", not "adding")
  5. Body wraps at 72 characters
  6. Body explains "what" and "why", not "how"

Documentation

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Code Quality

• Passes flake8

[ashb]

Looks good - one small change to make this easier for people to know how to use.

[ashb]

Could you extend the comment to say what fields are read from the secret?

[george-miller]

Definitely. How does this look @ashb ?

[george-miller]

@ashb Sorry to bother you. Mind looking at this again? Thanks!