$ git clone -n https://src.fedoraproject.org/rpms/rust-bytesize.git /var/lib/mock/f39-build-1455140-32912/root/chroot_tmpdir/scmroot/rust-bytesize
Cloning into '/var/lib/mock/f39-build-1455140-32912/root/chroot_tmpdir/scmroot/rust-bytesize'...
$ git fetch origin f048f6ada4bdc669e948301c0f1e65c9fba2de61:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/rust-bytesize
 * [new ref]         f048f6ada4bdc669e948301c0f1e65c9fba2de61 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at f048f6a Update to version 1.3.0; Fixes RHBZ#2234030