$ git clone -n https://src.fedoraproject.org/rpms/rust-serde_core.git /var/lib/mock/f45-build-44846-818/root/chroot_tmpdir/scmroot/rust-serde_core
Cloning into '/var/lib/mock/f45-build-44846-818/root/chroot_tmpdir/scmroot/rust-serde_core'...
$ git fetch origin afeae44a36d5fe41983a7da93006c7d1cc35bcc1:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/rust-serde_core
 * [new ref]         afeae44a36d5fe41983a7da93006c7d1cc35bcc1 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at afeae44 Update to version 1.0.229; Fixes RHBZ#2502141