$ git clone -n https://src.fedoraproject.org/rpms/rust-bitstream-io.git /var/lib/mock/f39-build-1866045-42552/root/chroot_tmpdir/scmroot/rust-bitstream-io
Cloning into '/var/lib/mock/f39-build-1866045-42552/root/chroot_tmpdir/scmroot/rust-bitstream-io'...
$ git fetch origin 738f03c4ee20d8864750e38ac9f252bfa0e80262:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/rust-bitstream-io
 * [new ref]         738f03c4ee20d8864750e38ac9f252bfa0e80262 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 738f03c Update to version 1.8.0; Fixes RHBZ#2247675