[AIRFLOW-6323] Remove non-ascii characters from default config

[mik-laj]

Line 126 in the default configuration file has characters in a comment outside of ASCII:

They appeared in this commit:

[https://github.com/apache/airflow/commit/a44e5762c394b59566e757c9c20cb3f9fd7851eb]

When running a vanilla install of Airflow using Python 2.7 and running the initdb command the following failure will occur:
{code:java}
File "/home/ubuntu/.airflow/local/lib/python2.7/site-packages/backports/configparser/init.py", line 1035, in _read
for lineno, line in enumerate(fp, start=1):
File "/home/ubuntu/.airflow/lib/python2.7/encodings/ascii.py", line 26, in decode
return codecs.ascii_decode(input, self.errors)[0]
UnicodeDecodeError: 'ascii' codec can't decode byte 0xe2 in position 1: ordinal not in range(128)
{code}

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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-6323
  • 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.
  • In case you are proposing a fundamental code change, you need to create an Airflow Improvement Proposal (AIP).
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Tests

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

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  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

[codecov-io]

Codecov Report

Merging #6878 into master will decrease coverage by 0.05%.
The diff coverage is n/a.

@@            Coverage Diff             @@
##           master    #6878      +/-   ##
==========================================
- Coverage   84.39%   84.33%   -0.06%     
==========================================
  Files         680      680              
  Lines       38501    38501              
==========================================
- Hits        32491    32468      -23     
- Misses       6010     6033      +23

Impacted Files	Coverage Δ
airflow/kubernetes/volume_mount.py	44.44% <0%> (-55.56%)	⬇️
airflow/kubernetes/volume.py	52.94% <0%> (-47.06%)	⬇️
airflow/kubernetes/pod_launcher.py	45.25% <0%> (-46.72%)	⬇️
airflow/kubernetes/refresh_config.py	50.98% <0%> (-23.53%)	⬇️
...rflow/contrib/operators/kubernetes_pod_operator.py	78.75% <0%> (-20%)	⬇️
airflow/jobs/backfill_job.py	91.88% <0%> (+0.28%)	⬆️
airflow/hooks/dbapi_hook.py	91.73% <0%> (+0.82%)	⬆️
airflow/models/connection.py	68.78% <0%> (+0.97%)	⬆️
airflow/hooks/hive_hooks.py	77.6% <0%> (+1.52%)	⬆️
airflow/utils/sqlalchemy.py	96.61% <0%> (+6.77%)	⬆️
... and 2 more

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