Backport "Drop phase.isTyper use in isLegalPrefix/asf" to 3.3 LTS#121

tgodzik wants to merge 4 commits intobackport-lts-3.3-21974scala/scala3-lts:backport-lts-3.3-21974from

backport-lts-3.3-21954scala/scala3-lts:backport-lts-3.3-21954Copy head branch name to clipboard