$ git clone -n https://github.com/xcp-ng-rpms/libssh2.git /var/lib/mock/v8.3-u-pcoval2-10063-28697/root/chroot_tmpdir/scmroot/libssh2
Cloning into '/var/lib/mock/v8.3-u-pcoval2-10063-28697/root/chroot_tmpdir/scmroot/libssh2'...
$ git fetch origin 31653fd00c336cceee396d7b8feaf045df48d832:KOJI_FETCH_HEAD
From https://github.com/xcp-ng-rpms/libssh2
 * [new ref]         31653fd00c336cceee396d7b8feaf045df48d832 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 31653fd bump release for test build