[AIRFLOW-2495] Bump up celery to >= 4.1.1 to get dependency on kombu >= 4.2.0

[rodrigc]

JIRA

• My PR addresses the following Airflow JIRA issues and references them in the PR title.
  • https://issues.apache.org/jira/browse/AIRFLOW-2495

Description

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Bump up celery to >= 4.1.1 to get dependency on kombu >= 4.2.0

This allows broker_url with sqla to work. kombu 4.0.2 does not support sqla urls.

Make sure you have checked all steps below.

Tests

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

Commits

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  1. Subject is separated from body by a blank line
  2. Subject is limited to 50 characters
  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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  • When adding new operators/hooks/sensors, the autoclass documentation generation needs to be added.

Code Quality

• Passes git diff upstream/master -u -- "*.py" | flake8 --diff

[codecov-io]

Codecov Report

Merging #3388 into master will not change coverage.
The diff coverage is n/a.

@@           Coverage Diff           @@
##           master    #3388   +/-   ##
=======================================
  Coverage   76.49%   76.49%           
=======================================
  Files         203      203           
  Lines       15019    15019           
=======================================
  Hits        11489    11489           
  Misses       3530     3530

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[kaxil]

LGTM. The errors in CI look unrelated

[rodrigc]

@kaxil Thanks for merging. What is the procedure to merge this to v1-10-test?
I am doing extensive testing of that branch now, and need this fix in that branch. Thanks again.

[cloneluke]

#3437