$ git clone -n https://src.fedoraproject.org/rpms/frozen-bubble.git /var/lib/mock/f39-build-1636119-39900/root/chroot_tmpdir/scmroot/frozen-bubble
Cloning into '/var/lib/mock/f39-build-1636119-39900/root/chroot_tmpdir/scmroot/frozen-bubble'...
$ git fetch origin 7a83833dfd5a7ca9125ddce327e23f1b3699c6cc:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/frozen-bubble
 * [new ref]         7a83833dfd5a7ca9125ddce327e23f1b3699c6cc -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 7a83833 Rebuilt for https://fedoraproject.org/wiki/Fedora_39_Mass_Rebuild