$ git clone -n https://src.fedoraproject.org/rpms/gnome-online-accounts.git /var/lib/mock/f39-build-2269039-54752/root/chroot_tmpdir/scmroot/gnome-online-accounts
Cloning into '/var/lib/mock/f39-build-2269039-54752/root/chroot_tmpdir/scmroot/gnome-online-accounts'...
$ git fetch origin efc9da2979653691c5a3d626355bcb45347d465d:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/gnome-online-accounts
 * [new ref]         efc9da2979653691c5a3d626355bcb45347d465d -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at efc9da2 Revert "Fix build with libxml2 2.12"