$ git clone -n https://src.fedoraproject.org/rpms/rust-libmimalloc-sys.git /var/lib/mock/epel9-build-side-110744-59079597-6570907/root/chroot_tmpdir/scmroot/rust-libmimalloc-sys
Cloning into '/var/lib/mock/epel9-build-side-110744-59079597-6570907/root/chroot_tmpdir/scmroot/rust-libmimalloc-sys'...
$ git fetch origin c8b93b1d48af7a9c68ca40bc398e0a2b0ecd1de2:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/rust-libmimalloc-sys
 * [new ref]         c8b93b1d48af7a9c68ca40bc398e0a2b0ecd1de2 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at c8b93b1 Update to 0.1.42; Fixes: RHBZ#2353251