$ git clone -n https://src.fedoraproject.org/rpms/rust-gdk4.git /var/lib/mock/f40-build-2660097-66918/root/chroot_tmpdir/scmroot/rust-gdk4
Cloning into '/var/lib/mock/f40-build-2660097-66918/root/chroot_tmpdir/scmroot/rust-gdk4'...
$ git fetch origin 5098b9920d499edd3882031f55ae84a8945430a3:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/rust-gdk4
 * [new ref]         5098b9920d499edd3882031f55ae84a8945430a3 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 5098b99 Update to version 0.8.1; Fixes RHBZ#2262611