arrow

ARROW-8826: [Crossbow] remote URL should always have .git

Since crossbow doesn't have tests, I was afraid to poke at the python code for fear of breaking something else, so I've tried to work around the inconsistency in the Travis scripts. What's one more `sed` anyway?

Closes #7411 from nealrichardson/fix-homebrew-remote

Authored-by: Neal Richardson <neal.p.richardson@gmail.com>
Signed-off-by: Neal Richardson <neal.p.richardson@gmail.com>