ENH: don't install jq dependency on windows

[jsheunis]

jq building is failing on windows during appveyor testing.

• Tried --ignore= and --ignore-glob= flags unsuccessfully in appveyour cmd calls.
• Tried using git-bash unsuccessfully.

This PR ensures:

• jq is not installed on windows (add below to setup.cfg)

install_requires
   jq;platform_system!='Windows'

• that the workflows.py module and related test_workflow.py are not collected by pytest on windows (added conf.py with content below:)

import platform

if platform.system() == 'Windows':
    collect_ignore_glob = ["*workflow.py", "*workflows.py"]

[codecov-commenter]

Codecov Report

Base: 82.47% // Head: 82.75% // Increases project coverage by +0.28% 🎉

Coverage data is based on head (601a6a5) compared to base (06623fb).
Patch coverage: 75.00% of modified lines in pull request are covered.

Additional details and impacted files

@@            Coverage Diff             @@
##             main     #248      +/-   ##
==========================================
+ Coverage   82.47%   82.75%   +0.28%     
==========================================
  Files          25       26       +1     
  Lines        1603     1606       +3     
==========================================
+ Hits         1322     1329       +7     
+ Misses        281      277       -4     

Flag	Coverage Δ
unittests	69.25% <75.00%> (+0.01%)	⬆️

Flags with carried forward coverage won't be shown. Click here to find out more.

Impacted Files	Coverage Δ
conftest.py	66.66% <66.66%> (ø)
datalad_catalog/tests/test_workflow.py	99.17% <100.00%> (+<0.01%)	⬆️
datalad_catalog/_version.py	46.59% <0.00%> (+1.59%)	⬆️

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[jsheunis]

Closes #224