$ git clone -n https://src.fedoraproject.org/rpms/plasma-activities.git /var/lib/mock/f40-build-788653-135301/root/chroot_tmpdir/scmroot/plasma-activities
Cloning into '/var/lib/mock/f40-build-788653-135301/root/chroot_tmpdir/scmroot/plasma-activities'...
$ git fetch origin cbecbafcdf0e6a2f5b3f2f6bffedd2b4836daea9:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/plasma-activities
 * [new ref]         cbecbafcdf0e6a2f5b3f2f6bffedd2b4836daea9 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at cbecbaf 6.0.0