This test was failing on Alpine's CI which had 'git' but wasn't in a git repo:
036b6a1262 (commitcomment-180001647)
Updates #12614
Change-Id: Ic1b8856aaf020788a2a57e48738851e13ea85a93
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
(cherry picked from commit ac19bd5e7a1791af621dfd04d98f627817bbefc9)