add python 3.12 to CI

[FabianHofmann]

[codecov[bot]]

Codecov Report

Attention: Patch coverage is 66.66667% with 2 lines in your changes are missing coverage. Please review.

Project coverage is 84.11%. Comparing base (1e1a123) to head (4972924).

Files	Patch %	Lines
linopy/solvers.py	66.66%	2 Missing :warning:

Additional details and impacted files

@@            Coverage Diff             @@
##           master     #184      +/-   ##
==========================================
- Coverage   88.87%   84.11%   -4.76%     
==========================================
  Files          15       15              
  Lines        3666     3671       +5     
  Branches      860      862       +2     
==========================================
- Hits         3258     3088     -170     
- Misses        283      464     +181     
+ Partials      125      119       -6     

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[maurerle]

Just to mention that the latest commit messages states to "disable cplex for python < 3.12" while it actually does the opposite (disable it for python >= 3.12). So you might want to --amend that and force push the commit message @FabianHofmann :)