$ git clone -n https://src.fedoraproject.org/rpms/yarnpkg.git /var/lib/mock/f40-build-797505-141357/root/chroot_tmpdir/scmroot/yarnpkg
Cloning into '/var/lib/mock/f40-build-797505-141357/root/chroot_tmpdir/scmroot/yarnpkg'...
$ git fetch origin 9fc9e8350c22f701d8946c079fcf20021a30cbd4:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/yarnpkg
 * [new ref]         9fc9e8350c22f701d8946c079fcf20021a30cbd4 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 9fc9e83 Update to 1.22.22