test: Add various tests for open issues

[lukemanley]

tests added for open issues that appear to be fixed but untested:

closes #15122
closes #15145
closes #15546
closes #15574
closes #16296
closes #17669
closes #18244
closes #18369

open issues that appear to be fixed and already tested (noting tests in order to close):

closes #19528 - test_concat.py::test_concat_invalid_schema_err_20355
closes #15347 - test_join_asof.py::test_join_asof_not_sorted

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 79.26%. Comparing base (3336475) to head (5fd30ce).
Report is 9 commits behind head on main.

Additional details and impacted files

@@            Coverage Diff             @@
##             main   #21075      +/-   ##
==========================================
+ Coverage   79.20%   79.26%   +0.06%     
==========================================
  Files        1586     1586              
  Lines      225648   225676      +28     
  Branches     2588     2588              
==========================================
+ Hits       178714   178889     +175     
+ Misses      46344    46197     -147     
  Partials      590      590              

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