$ git clone -n https://github.com/xcp-ng-rpms/swtpm.git /var/lib/mock/v8.3-u-prebuild-9275-28057/root/chroot_tmpdir/scmroot/swtpm
Cloning into '/var/lib/mock/v8.3-u-prebuild-9275-28057/root/chroot_tmpdir/scmroot/swtpm'...
$ git fetch origin 03cc0529549191da6e3813694db2b962a5e9c151:KOJI_FETCH_HEAD
From https://github.com/xcp-ng-rpms/swtpm
 * [new ref]         03cc0529549191da6e3813694db2b962a5e9c151 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 03cc052 bump release for test build