$ git clone -n https://src.fedoraproject.org/rpms/xnec2c.git /var/lib/mock/f45-build-38993-731/root/chroot_tmpdir/scmroot/xnec2c
Cloning into '/var/lib/mock/f45-build-38993-731/root/chroot_tmpdir/scmroot/xnec2c'...
$ git fetch origin 938bd5b6a9a7897e45cba0d22591926af1f8fd5c:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/xnec2c
 * [new ref]         938bd5b6a9a7897e45cba0d22591926af1f8fd5c -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 938bd5b Rebuilt for https://fedoraproject.org/wiki/Fedora_45_Mass_Rebuild