1. Create new Content Type named "Test 1" with "Name" and "Single relation" fields.
2. Create new Content Type named "Test 2" with "Name" and "Single relation" fields.
3. Create single Content of "Test 1" CT and single Content of "Test 2" in "Folder 1".
4. Create bidirectional relation between those two Contents (Test 1 => Test 2, Test 2 => Test 1).
5. Enter "Folder 1" in Content Tree.

Result:
GraphQL module throws 500 exception (nesting or OOM).

Expected result:
GraphQL module shouldn't throw an exception.