$ git clone -n https://src.fedoraproject.org/rpms/rust2rpm.git /var/lib/mock/f39-build-1562900-37465/root/chroot_tmpdir/scmroot/rust2rpm
Cloning into '/var/lib/mock/f39-build-1562900-37465/root/chroot_tmpdir/scmroot/rust2rpm'...
$ git fetch origin d6b57437f6d17510921e0eee087a315924bc5dc2:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/rust2rpm
 * [new ref]         d6b57437f6d17510921e0eee087a315924bc5dc2 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at d6b5743 Update to version 25.0.1; Fixes RHBZ#2244803