Add packaging to setup_requires, and use >= to play nice to setup.py (fixes #1625)

[hartwork]

Fixes unfixed (but closed) issue #1625, more details at #1625 (comment) . Thanks! 🙏

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[codecov-commenter]

Codecov Report

Merging #1780 (80a7211) into master (bba31cd) will increase coverage by 0.01%.
The diff coverage is n/a.

@@            Coverage Diff             @@
##           master    #1780      +/-   ##
==========================================
+ Coverage   94.28%   94.29%   +0.01%     
==========================================
  Files          74       74              
  Lines       15696    15696              
==========================================
+ Hits        14799    14801       +2     
+ Misses        897      895       -2     

Impacted Files	Coverage Δ
setup.py	0.00% <ø> (ø)
tests/test_cluster.py	98.67% <0.00%> (ø)
tests/conftest.py	92.89% <0.00%> (+1.01%)	⬆️

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[chayim]

Thank you for your contribution @hartwork. Admittedly we don't currently test for a pip install of the package (automatically), though I think we should. It would also help when updates (like this) are missed by me. Much thanks! Merging.