[AIRFLOW-XXX] Update Alembic autogenerator to pass pylint

[ashb]

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Jira

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Description

• Update the template alembic uses for creating migrations to pass (or at least be closer to passing) pylint checks

[codecov-io]

Codecov Report

Merging #6216 into master will decrease coverage by 0.01%.
The diff coverage is n/a.

@@            Coverage Diff             @@
##           master    #6216      +/-   ##
==========================================
- Coverage   80.02%   80.01%   -0.02%     
==========================================
  Files         610      610              
  Lines       35176    35176              
==========================================
- Hits        28151    28147       -4     
- Misses       7025     7029       +4

Impacted Files	Coverage Δ
airflow/contrib/operators/ssh_operator.py	82.5% <0%> (-1.25%)	⬇️
airflow/utils/dag_processing.py	56.37% <0%> (-0.52%)	⬇️

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[potiuk]

Nit: Should we split it to two separate commits? Filtering out of Flask Appbuilder tables should be separate commit I think.

[ashb]

Nit: Should we split it to two separate commits? Filtering out of Flask Appbuilder tables should be separate commit I think.

Good call, will do as two separate PRs. Done, other PR #6221