Query: collection join scenario where inner collection is a group by correlated with outer should be detected and blocked

[maumar]

Example:

 ctx.Customers.Where(c => c.CustomerID.StartsWith("A"))
    .Select(c => c.Orders.GroupBy(o => o.OrderID).Select(g => g.Key).ToArray());

when processing collection join we try to add correlation predicate columns to the inner projection, however that produces incorrect sql - group by query can only project grouping keys (and aggregates).
Outer key can't be part of the grouping either (Each GROUP BY expression must contain at least one column that is not an outer reference.)

Uncorrelated group by subqueries should still work.