Add headers argument to RequestTestCaseMixin.request method

[yakky]

Description

RequestTestCaseMixin.request now accepts headers dict and pass it to RequestFactory

References

Fix #290

Checklist

• I have read the contribution guide
• Code lint checked via inv lint
• changes file included (see docs)
• Usage documentation added in case of new features
• Tests added

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 92.30%. Comparing base (3ce2962) to head (fef062f).
Report is 1 commits behind head on develop.

Additional details and impacted files

@@           Coverage Diff            @@
##           develop     #291   +/-   ##
========================================
  Coverage    92.30%   92.30%           
========================================
  Files           10       10           
  Lines          806      806           
  Branches       127      127           
========================================
  Hits           744      744           
  Misses          24       24           
  Partials        38       38           

Flag	Coverage Δ
unittests	92.30% <100.00%> (ø)

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