add support for analyzing pseudo-classes

[bartveneman]

closes #432

[codecov-commenter]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 99.86%. Comparing base (9372da6) to head (88d64d8).

Additional details and impacted files

@@           Coverage Diff           @@
##           master     #433   +/-   ##
=======================================
  Coverage   99.86%   99.86%           
=======================================
  Files          18       18           
  Lines        2210     2239   +29     
=======================================
+ Hits         2207     2236   +29     
  Misses          3        3           

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[codecov-commenter]

Bundle Report

Changes will increase total bundle size by 168.04kB (100.0%) ⬆️⚠️, exceeding the configured threshold of 5%.

Bundle name	Size	Change
analyzeCss-analyzeCss-esm	99.64kB	99.64kB (100%) ⬆️⚠️
analyzeCss-analyzeCss-esm-analyzeCss-umd	68.4kB	68.4kB (100%) ⬆️⚠️