$ git clone -n https://src.fedoraproject.org/rpms/R-hms.git /var/lib/mock/f40-build-1944476-25177/root/chroot_tmpdir/scmroot/R-hms
Cloning into '/var/lib/mock/f40-build-1944476-25177/root/chroot_tmpdir/scmroot/R-hms'...
$ git fetch origin 63cd15a4fc286f9ffa2cebdf5f655ae94363cb7f:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/R-hms
 * [new ref]         63cd15a4fc286f9ffa2cebdf5f655ae94363cb7f -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 63cd15a R-maint-sig mass rebuild