[AIRFLOW-3900] Error on undefined template variables in unit tests.

[jmcarp]

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  • https://issues.apache.org/jira/browse/AIRFLOW-3900
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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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Documentation

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  • When adding new operators/hooks/sensors, the autoclass documentation generation needs to be added.
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Code Quality

• Passes flake8

[codecov-io]

Codecov Report

Merging #4719 into master will not change coverage.
The diff coverage is n/a.

@@           Coverage Diff           @@
##           master    #4719   +/-   ##
=======================================
  Coverage   74.65%   74.65%           
=======================================
  Files         430      430           
  Lines       27974    27974           
=======================================
  Hits        20884    20884           
  Misses       7090     7090

Impacted Files	Coverage Δ
airflow/contrib/operators/ssh_operator.py	82.05% <0%> (-1.29%)	⬇️
airflow/models/__init__.py	92.84% <0%> (+0.05%)	⬆️

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[ashb]

This one doesn't seem like an easy one to cherry-pick in to 1.10.3, so we might leave it https://travis-ci.org/ashb/airflow/jobs/508434072

(I tried applying it to both flask-admin and FAB backends, and both of them had failures)

@jmcarp If you want this in 1.10.3 could you open a PR targeting the v1-10-stable branch please? Otherwise I'll mark at as 2.0.0 only.

[jmcarp]

I think it's fine to hold off until 2.0. My main goal here was to avoid template regressions, and as long as this commit is in master, I think we'll do that.