[AIRFLOW-7066] Use sphinx syntax in concepts.rst

[zhongjiajie]

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Issue link: AIRFLOW-7066

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[zhongjiajie]

Seem CI failed with unrelated error, https://travis-ci.org/github/apache/airflow/jobs/662646733?utm_medium=notification&utm_source=github_status

[potiuk]

Restarted

[zhongjiajie]

BTW, I have some question could not understand, in my PR #7709, raise pylint error three time, but airflow/www/views.py is in pylint_todo.txt, which mean will not test by pylint, also test folder will not test by pylint. should where the pylint error? (I only change two files)

I test in breeze using pylint airflow/www/views.py and pylint test/www/views.py only airflow/www/views.py have some error hint(but it in pylint_todo.txt)
@potiuk

[codecov-io]

Codecov Report

Merging #7729 into master will not change coverage by %.
The diff coverage is n/a.

@@           Coverage Diff           @@
##           master    #7729   +/-   ##
=======================================
  Coverage   86.93%   86.93%           
=======================================
  Files         915      915           
  Lines       44158    44158           
=======================================
  Hits        38387    38387           
  Misses       5771     5771           

Impacted Files	Coverage Δ
...w/example_dags/example_latest_only_with_trigger.py	100.00% <ø> (ø)
airflow/example_dags/example_subdag_operator.py	100.00% <ø> (ø)
airflow/example_dags/subdags/subdag.py	100.00% <ø> (ø)

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[potiuk]

BTW, I have some question could not understand, in my PR #7709, raise pylint error three time, but airflow/www/views.py is in pylint_todo.txt, which mean will not test by pylint, also test folder will not test by pylint. should where the pylint error? (I only change two files)

I test in breeze using pylint airflow/www/views.py and pylint test/www/views.py only airflow/www/views.py have some error hint(but it in pylint_todo.txt)
@exploy

It is the test/ that is failing. We have two separate pre-commits - pylint and pylint-test . The test one is failing in the other build and should be fixed there.

[potiuk]

Thanks @zhongjiajie !

[zhongjiajie]

BTW, I have some question could not understand, in my PR #7709, raise pylint error three time, but airflow/www/views.py is in pylint_todo.txt, which mean will not test by pylint, also test folder will not test by pylint. should where the pylint error? (I only change two files)
I test in breeze using pylint airflow/www/views.py and pylint test/www/views.py only airflow/www/views.py have some error hint(but it in pylint_todo.txt)
@exploy

It is the test/ that is failing. We have two separate pre-commits - pylint and pylint-test . The test one is failing in the other build and should be fixed there.

Ok, will take a look to the test, BTW, thanks for merging