[AIRFLOW-1321] Fix hidden field key to ignore case

[sekikn]

Dear Airflow maintainers,

Please accept this PR. I understand that it will not be reviewed until I have checked off all the steps below!

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-1321

Description

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

Webserver has a feature to hide sensitive variable fields,
which key contain specific words. But its matching is
case-sensitive, so "google_api_key" is hidden but
"GOOGLE_API_KEY" is not. This behaviour is not intuitive,
so this PR fixes it to be case-insensitive.

Tests

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

Added tests/www/test_utils.py.
In addition, I confirmed the feature behaved expectedly as the following screenshot:

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
  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"

[codecov-io]

Codecov Report

Merging #2400 into master will decrease coverage by 0.02%.
The diff coverage is 60%.

@@            Coverage Diff             @@
##           master    #2400      +/-   ##
==========================================
- Coverage   69.26%   69.23%   -0.03%     
==========================================
  Files         146      146              
  Lines       11231    11231              
==========================================
- Hits         7779     7776       -3     
- Misses       3452     3455       +3

Impacted Files	Coverage Δ
airflow/www/views.py	67.62% <0%> (ø)	⬆️
airflow/www/utils.py	78.88% <100%> (+0.72%)	⬆️
airflow/jobs.py	74.87% <0%> (-0.41%)	⬇️

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[msumit]

@sekikn +1 for moving sensitive field list from views to utils.

Please update your commit message as per the below guidelines, then you are all good:

i. Subject is separated from body by a blank line
ii. Subject is limited to 50 characters

[sekikn]

Thanks for the review @msumit! Updated the subject within 50 characters.

[saguziel]

lgtm