GitHub actions

[DerWeh]

Migrate from Travis to GitHub actions, as Travis is not free anymore.

[codecov]

Codecov Report

Merging #20 (e758cae) into develop (812bc4c) will decrease coverage by 0.05%.
The diff coverage is 62.50%.

❗ Current head e758cae differs from pull request most recent head 412aa1b. Consider uploading reports for the commit 412aa1b to get more accurate results

@@             Coverage Diff             @@
##           develop      #20      +/-   ##
===========================================
- Coverage    83.33%   83.28%   -0.06%     
===========================================
  Files           27       27              
  Lines         1578     1597      +19     
  Branches       141      143       +2     
===========================================
+ Hits          1315     1330      +15     
- Misses         215      217       +2     
- Partials        48       50       +2     

Impacted Files	Coverage Δ
gftool/density.py	79.48% <ø> (ø)
gftool/pade.py	42.19% <16.66%> (ø)
gftool/linalg.py	83.33% <66.66%> (-6.15%)	⬇️
gftool/lattice/bethe.py	98.46% <100.00%> (+0.42%)	⬆️
gftool/cpa.py	89.01% <0.00%> (-2.20%)	⬇️

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