$ git clone -n https://src.fedoraproject.org/rpms/rust-thiserror.git /var/lib/mock/f41-build-side-1-3134289-39731/root/chroot_tmpdir/scmroot/rust-thiserror
Cloning into '/var/lib/mock/f41-build-side-1-3134289-39731/root/chroot_tmpdir/scmroot/rust-thiserror'...
$ git fetch origin 541fa5f07f9effd6d75da78aab2f17f3539b500b:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/rust-thiserror
 * [new ref]         541fa5f07f9effd6d75da78aab2f17f3539b500b -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 541fa5f Update to version 1.0.69