CompatHelper: bump compat for JuMP to 0.23, (keep existing compat)

[github-actions]

This pull request changes the compat entry for the JuMP package from 0.21 to 0.21, 0.23.
This keeps the compat entries for earlier versions.

Note: I have not tested your package with this new compat entry.
It is your responsibility to make sure that your package tests pass before you merge this pull request.

[codecov-commenter]

Codecov Report

Merging #29 (2396af5) into main (1a472b2) will decrease coverage by 0.33%.
The diff coverage is n/a.

@@            Coverage Diff             @@
##             main      #29      +/-   ##
==========================================
- Coverage   97.87%   97.54%   -0.34%     
==========================================
  Files           1        1              
  Lines         188      122      -66     
==========================================
- Hits          184      119      -65     
+ Misses          4        3       -1     

Impacted Files	Coverage Δ
src/TravelingSalesmanExact.jl	97.54% <0.00%> (-0.34%)	⬇️

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