$ git clone -n https://src.fedoraproject.org/rpms/libwebp.git /var/lib/mock/eln-build-side-114853-61003527-6587542/root/chroot_tmpdir/scmroot/libwebp
Cloning into '/var/lib/mock/eln-build-side-114853-61003527-6587542/root/chroot_tmpdir/scmroot/libwebp'...
$ git fetch origin 2d3b6b03f2c5b6dd85935dc451c5742883595858:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/libwebp
 * [new ref]         2d3b6b03f2c5b6dd85935dc451c5742883595858 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 2d3b6b0 Update to 1.6.0