release-74-rc
ICU-21697 Convert ICU Site pages to markdown for Github Pages
ICU-22324 Add docs for Maven usage
ICU-22324 Update BRS task docs
ICU-20088 User Guide migration: Add navigation structure and TOC for Jekyll, fix formatting issues, etc.
ICU-22194 Add CI job to generate Github Pages using Github Actions
ICU-21310 replacement User Guide main index page