Bump regex from 1.4.3 to 1.5.5 in /ci/date-check (#1364)
Bump regex from 1.4.3 to 1.5.5 in /ci/date-check (#1364)

Co-authored-by: dependabot[bot] <1c358da00a777d4e9898c1280ab801e2df165188@users.noreply.github.com>
rust-lang/rustc-dev-guide,rust-lang/rustc-dev-guide,rust-lang/rustc-dev-guide,rust-lang/rustc-dev-guide