[AIRFLOW-5365] No need to do image rebuild when switching master/v1-1…

[potiuk]

…0-test

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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-5365

Description

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

Pre-commits should work now smoothly (no rebuilds triggered) when switching between master
and v1-10-test.

Tests

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

Commits

• My commits all reference Jira issues in their subject lines, and I have squashed multiple commits if they address the same issue. In addition, my commits follow the guidelines from "How to write a good git commit message":
  1. Subject is separated from body by a blank line
  2. Subject is limited to 50 characters (not including Jira issue reference)
  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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  • All the public functions and the classes in the PR contain docstrings that explain what it does
  • If you implement backwards incompatible changes, please leave a note in the Updating.md so we can assign it to a appropriate release

Code Quality

• Passes flake8

[potiuk]

@kaxil @ashb - this one is really useful when cherry-picking and switching between branches.

[potiuk]

Again here - it is rather small change and simple to review but as result any kind of cherry-picking is great and fully integrates with pre-commits while cherry-picking - so if we merge #5979 together with it we might save ton of time for cherry-picking python2 problems.