$ git clone -n https://src.fedoraproject.org/rpms/plasma-welcome.git /var/lib/mock/f41-build-1012478-17768/root/chroot_tmpdir/scmroot/plasma-welcome
Cloning into '/var/lib/mock/f41-build-1012478-17768/root/chroot_tmpdir/scmroot/plasma-welcome'...
$ git fetch origin f2e72b37aa086bba296d03892e5852747deaa0be:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/plasma-welcome
 * [new ref]         f2e72b37aa086bba296d03892e5852747deaa0be -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at f2e72b3 6.1.0