Use ssh for git-upload-pack

Currently git-upload-pack is executed via an unauthenticated https
call. This doesn't work if the project is not world readable.
Switching git-upload-pack to use ssh like all other commands resolves
this issue.

This is a port of I26bc6c8937a6b8cdd2577f32c67b708211144fbd to zuulv3
branch.

Change-Id: If3541faf1f866a40d750c9c899f399a14bf30553
2 files changed