Commit range reference links result in a broken compare page

See https://gitlab.com/gitlab-org/gitlab-ce/issues/34323#note_38534226, the link points to https://gitlab.com/gitlab-org/gitlab-ce/compare/e46a3d2fda47f96885b38c6c6caf7dc3e0df19bd%5E...88892e43adecd68de7940fdc9856a4557098cb6c (note the %5E ^ encoding) which is broken.

I can't remember if we always encoded the ^ character and the comparison page just isn't decoding it properly now, which would make this Platform, or if we're erroneously encoding the character in Banzai.

cc @DouweM