Feature: speed up learning tests

[emhbrine]

Using setUpClass instead of setUp in unit tests so that the setup is done once per class rather than before each test. This is especially important for TestMapSelector since using MixedLM is expensive.

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Comparison is base (77b0edc) 78.80% compared to head (46aab8d) 78.28%.
Report is 1 commits behind head on develop.

Additional details and impacted files

@@             Coverage Diff             @@
##           develop    #1343      +/-   ##
===========================================
- Coverage    78.80%   78.28%   -0.53%     
===========================================
  Files           62       62              
  Lines         5762     5762              
===========================================
- Hits          4541     4511      -30     
- Misses        1221     1251      +30     

see 3 files with indirect coverage changes