Fix case sensitivity in enum parsers

[GabrielKS]

parse_enum_mapping was converting input to uppercase but the keys of the underlying dictionary were not all uppercase, so, e.g., parse_enum_mapping(PrimeMovers, "PVe") wouldn't work and #849 wasn't truly solved. Now everything is Unicode.normalize(casefold=true)'d on both sides.

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Comparison is base (9d6e1bf) 85.38% compared to head (d33e2f8) 85.38%.

Additional details and impacted files

@@           Coverage Diff           @@
##             main    #1045   +/-   ##
=======================================
  Coverage   85.38%   85.38%           
=======================================
  Files         170      170           
  Lines        7689     7689           
=======================================
  Hits         6565     6565           
  Misses       1124     1124           

Flag	Coverage Δ
unittests	85.38% <100.00%> (ø)

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Files	Coverage Δ
src/parsers/common.jl	66.66% <100.00%> (ø)