$ git clone -n https://src.fedoraproject.org/rpms/libguestfs.git /var/lib/mock/f39-build-2450560-61041/root/chroot_tmpdir/scmroot/libguestfs
Cloning into '/var/lib/mock/f39-build-2450560-61041/root/chroot_tmpdir/scmroot/libguestfs'...
$ git fetch origin 345e2a7513f623b17bb9ddb4ff5a4f3c3fd55cbe:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/libguestfs
 * [new ref]         345e2a7513f623b17bb9ddb4ff5a4f3c3fd55cbe -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 345e2a7 New upstream stable branch version 1.52.0