[AIRFLOW-4901] Relaxes jinja2 version requirement

[purew]

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Jira

• My PR addresses the following Airflow Jira issues and references them in the PR title. For example, "[AIRFLOW-XXX] My Airflow PR"
  • Fixes https://issues.apache.org/jira/browse/AIRFLOW-4901
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Description

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  Relaxes jinja version requirement so that pipenv can install airflow.

Tests

• My PR adds the following unit tests OR does not need testing for this extremely good reason:
  PR merely relaxes a jinja version constraint.

Commits

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  1. Subject is separated from body by a blank line
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  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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Code Quality

• Passes flake8

[codecov-io]

Codecov Report

Merging #5556 into master will not change coverage.
The diff coverage is n/a.

@@          Coverage Diff           @@
##           master   #5556   +/-   ##
======================================
  Coverage      79%     79%           
======================================
  Files         489     489           
  Lines       30726   30726           
======================================
  Hits        24275   24275           
  Misses       6451    6451

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[pgagnon]

@ashb

[ashb]

2.10.1 is a security fix on 2.10.0 so no, afraid not. - https://github.com/pallets/jinja/blob/master/CHANGES.rst#version-2101

[pgagnon]

@purew Are you able to find a way to fix this further down the dependency graph? This is problematic. 😕

[ashb]

See also pypa/pipenv#2596 - the dependency solver in pipenv isn't without it's problems and that might be what is happening here.

[purew]

@pgagnon We're running airflow inside a secure environment so I wont dig deeper into this. I'll use this fork and the insecure jinja version until it's been solved upstream.