$ git clone -n https://src.fedoraproject.org/rpms/rust-regex-test.git /var/lib/mock/f40-build-1897476-25065/root/chroot_tmpdir/scmroot/rust-regex-test
Cloning into '/var/lib/mock/f40-build-1897476-25065/root/chroot_tmpdir/scmroot/rust-regex-test'...
$ git fetch origin 5189dd4fa256c27a1d59fe4a3236485bd11fefea:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/rust-regex-test
 * [new ref]         5189dd4fa256c27a1d59fe4a3236485bd11fefea -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 5189dd4 Update to version 0.1.1; Fixes RHBZ#2291085