[AIRFLOW-6725] Simplify chaining operation in DagFileProcessorManager

[kaxil]

Simplify chaining operation in an IF condition

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Issue link: AIRFLOW-6725

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[mik-laj]

I accept it. But what will we do to prevent regression so that similar problems do not arise in the future? Cosmetic changes should be detected automatically because the OOS community cannot force rules otherwise.

[codecov-io]

Codecov Report

Merging #7349 into master will decrease coverage by 54.26%.
The diff coverage is 0%.

@@             Coverage Diff             @@
##           master    #7349       +/-   ##
===========================================
- Coverage   86.35%   32.09%   -54.27%     
===========================================
  Files         871      870        -1     
  Lines       40613    40600       -13     
===========================================
- Hits        35073    13030    -22043     
- Misses       5540    27570    +22030

Impacted Files	Coverage Δ
airflow/utils/dag_processing.py	24.71% <0%> (-63.41%)	⬇️
...low/contrib/operators/wasb_delete_blob_operator.py	0% <0%> (-100%)	⬇️
...ing_platform/example_dags/example_display_video.py	0% <0%> (-100%)	⬇️
airflow/contrib/hooks/vertica_hook.py	0% <0%> (-100%)	⬇️
airflow/contrib/sensors/__init__.py	0% <0%> (-100%)	⬇️
airflow/hooks/mssql_hook.py	0% <0%> (-100%)	⬇️
airflow/hooks/webhdfs_hook.py	0% <0%> (-100%)	⬇️
airflow/contrib/sensors/emr_base_sensor.py	0% <0%> (-100%)	⬇️
...irflow/contrib/operators/slack_webhook_operator.py	0% <0%> (-100%)	⬇️
airflow/hooks/jdbc_hook.py	0% <0%> (-100%)	⬇️
... and 741 more

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[kaxil]

I accept it. But what will we do to prevent regression so that similar problems do not arise in the future? Cosmetic changes should be detected automatically because the OOS community cannot force rules otherwise.

chained-comparison - This pylint rule should, in theory, take care of this.(pylint-dev/pylint#2046)

Need to dig in more detail on why it didn't check this, maybe the file is still not pylint compatible and hence in ignored! list