release_version was interpolated into an awk regex, where '.' matches any
character. Version 1.0.1-beta.1 therefore also admitted
.changes/released/1x0x1-betaX1/, letting the archive drift from the
CHANGELOG version while every other seal assertion still passed and
breaking the documented audit trail.
Compare the archive prefix with index() and split the basename off with
substr(), matching the literal-comparison idiom already used throughout
check-changelog-pr.sh. Only the basename, whose character class is fixed,
stays a pattern.
chichuan
c2c1131079