Conditionally depend on pandas in tests

[thomasjpfan]

Closes #5469

This PR updates the tests to conditionally dependent on pandas. With this PR the only code that uses pandas are maintenance, benchmark scripts, and two notebooks:

• scripts/check_all_tests_are_covered.py
• scripts/run_mypy.py
• benchmarks/benchmarks/benchmarks.py
• docs/source/learn/examples/GLM_linear.ipynb
• docs/source/learn/examples/pymc_overview.ipynb

[codecov]

Codecov Report

Merging #5633 (7e19704) into main (b895e40) will not change coverage.
The diff coverage is n/a.

@@           Coverage Diff           @@
##             main    #5633   +/-   ##
=======================================
  Coverage   87.63%   87.63%           
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  Files          76       76           
  Lines       13717    13717           
=======================================
  Hits        12021    12021           
  Misses       1696     1696           

[michaelosthege]

Do you want to remove pandas from the requirements.txt then?
Since it's only used in the tests, maybe that would have been enough. But the changes look good - just one file where you forgot this importskip thing

[ricardoV94]

@thomasjpfan May I ask what does CLN in your PR title stand for?

[thomasjpfan]

May I ask what does CLN in your PR title stand for?

It means "Clean". I like to tag my commits so they are easier to track down in the future.

That being said, I removed it from the PR title.

[michaelosthege]

Thanks, @thomasjpfan !

Lets hope this makes the life of conda/mamba dependency resolves a little less complicated.