$ git clone -n https://src.fedoraproject.org/rpms/rust-rfc2047-decoder.git /var/lib/mock/f39-build-1586185-38184/root/chroot_tmpdir/scmroot/rust-rfc2047-decoder
Cloning into '/var/lib/mock/f39-build-1586185-38184/root/chroot_tmpdir/scmroot/rust-rfc2047-decoder'...
$ git fetch origin 6ab1c687914f2e4812ec91f85b176967a7fe529e:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/rust-rfc2047-decoder
 * [new ref]         6ab1c687914f2e4812ec91f85b176967a7fe529e -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 6ab1c68 Rebuilt for https://fedoraproject.org/wiki/Fedora_39_Mass_Rebuild