$ git clone -n https://src.fedoraproject.org/rpms/rust-slotmap.git /var/lib/mock/f40-build-2157415-50929/root/chroot_tmpdir/scmroot/rust-slotmap
Cloning into '/var/lib/mock/f40-build-2157415-50929/root/chroot_tmpdir/scmroot/rust-slotmap'...
$ git fetch origin e4c0b9caa976cf0a3eae512dcf4c9ff635db6a0c:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/rust-slotmap
 * [new ref]         e4c0b9caa976cf0a3eae512dcf4c9ff635db6a0c -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at e4c0b9c Update to version 1.0.7; Fixes RHBZ#2252335