docs: Update the tutorial example w.r.t. cardinality
Since we now enforce link cardinality at time of `INSERT`, the example
needs an explicit `LIMIT 1`.
@@ -60,6 +60,9 @@ finished, we can omit the ``year`` and ``cast``, populating only the
......... # the last name is sufficient
......... # to identify the right person
......... .last_name = 'Villeneuve'
+ ......... # the LIMIT is needed to satisfy the single
+ ......... # link requirement validation
+ ......... LIMIT 1
......... )
......... };
{Object { id: <uuid>'64d024dc-54d5-11e9-8c54-a3f59e1d995e' }}
