nightly-2021-02-12

Changes since cade21:

Full commit log

• 18aaef4 chore: fix test
• 8320ab6 fix: syntax match: check identifiers (using strict equality)
• 19306a8 chore: delaborator: print BinderInfo.auxDecl as explicit
• 10bcd0b fix: #check_failure
• a74960a fix: delaborator: match with shadowing