$ git clone -n https://src.fedoraproject.org/rpms/rust-rmpv.git /var/lib/mock/f40-build-2101579-50511/root/chroot_tmpdir/scmroot/rust-rmpv
Cloning into '/var/lib/mock/f40-build-2101579-50511/root/chroot_tmpdir/scmroot/rust-rmpv'...
$ git fetch origin 017eec455d1ea0d7e321c01f0b810f8e56ed409e:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/rust-rmpv
 * [new ref]         017eec455d1ea0d7e321c01f0b810f8e56ed409e -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 017eec4 Update to version 1.0.1; Fixes RHBZ#2224605