[AIRFLOW-6168] allows proxyfix to be configurable

[timkpaine]

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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-XXX
  • In case you are fixing a typo in the documentation you can prepend your commit with [AIRFLOW-XXX], code changes always need a Jira issue.
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Description

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

Super straightforward, basically allows the kwargs to ProxyFix to be configured individually in the configuration file.

Tests

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

Added tests for the www/app.py for this feature

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

Documentation updated

[codecov-io]

Codecov Report

Merging #6723 into master will decrease coverage by 0.59%.
The diff coverage is n/a.

@@            Coverage Diff            @@
##           master    #6723     +/-   ##
=========================================
- Coverage   84.54%   83.95%   -0.6%     
=========================================
  Files         672      672             
  Lines       38081    38081             
=========================================
- Hits        32197    31971    -226     
- Misses       5884     6110    +226

Impacted Files	Coverage Δ
airflow/www/app.py	97.45% <ø> (+0.84%)	⬆️
airflow/operators/postgres_operator.py	0% <0%> (-100%)	⬇️
airflow/operators/mysql_operator.py	0% <0%> (-100%)	⬇️
airflow/operators/mysql_to_hive.py	0% <0%> (-100%)	⬇️
airflow/operators/generic_transfer.py	0% <0%> (-100%)	⬇️
airflow/executors/celery_executor.py	49.66% <0%> (-38.93%)	⬇️
airflow/utils/sqlalchemy.py	84.74% <0%> (-11.87%)	⬇️
airflow/executors/executor_loader.py	58.69% <0%> (-4.35%)	⬇️
airflow/hooks/dbapi_hook.py	88.13% <0%> (-3.39%)	⬇️
airflow/executors/base_executor.py	93.42% <0%> (-2.64%)	⬇️
... and 7 more

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