$ git clone -n https://src.fedoraproject.org/rpms/rust-jiter.git /var/lib/mock/f42-build-side-1-3589183-46954/root/chroot_tmpdir/scmroot/rust-jiter
Cloning into '/var/lib/mock/f42-build-side-1-3589183-46954/root/chroot_tmpdir/scmroot/rust-jiter'...
$ git fetch origin c92a097e1ce013a9d4d5429fb1a1d5663d268ec7:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/rust-jiter
 * [new ref]         c92a097e1ce013a9d4d5429fb1a1d5663d268ec7 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at c92a097 Update to version 0.10.0; Fixes RHBZ#2367124