t0021: tr portability fix for Solaris
t0021: tr portability fix for Solaris

Solaris' /usr/bin/tr doesn't seem to like multiple character
ranges in brackets (it simply prints "Bad string").

Instead, let's just enumerate the transformation we want.

Signed-off-by: Jeff King <696e3fbcf235d40b6ea1ebd61c87cbea79d444e7@peff.net>
Signed-off-by: Junio C Hamano <a6723cc3f76163bf7adb636a73ac3b0ceb3e6b9b@pobox.com>

destenson/git,destenson/git,destenson/git,destenson/git,destenson/git,destenson/git,destenson/git,destenson/git