$ git clone -n https://src.fedoraproject.org/rpms/rust-serde.git /var/lib/mock/f39-build-1851713-42271/root/chroot_tmpdir/scmroot/rust-serde
Cloning into '/var/lib/mock/f39-build-1851713-42271/root/chroot_tmpdir/scmroot/rust-serde'...
$ git fetch origin 91af3aef66668039cd9c87010e368d505da92898:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/rust-serde
 * [new ref]         91af3aef66668039cd9c87010e368d505da92898 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 91af3ae Update to version 1.0.192; Fixes RHBZ#2246257