$ git clone -n https://src.fedoraproject.org/rpms/boinc-client.git /var/lib/mock/f39-build-1466127-33647/root/chroot_tmpdir/scmroot/boinc-client
Cloning into '/var/lib/mock/f39-build-1466127-33647/root/chroot_tmpdir/scmroot/boinc-client'...
$ git fetch origin b2ea482579b41837cff67e9ee456f3fa4322fc03:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/boinc-client
 * [new ref]         b2ea482579b41837cff67e9ee456f3fa4322fc03 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at b2ea482 Rebuilt for https://fedoraproject.org/wiki/Fedora_39_Mass_Rebuild