N1QL insert/delete/update operations incorrectly authorized

To reproduce using build Enterprise Edition 5.0.0-1965 build 1965,

• Create a bucket closed1 with a password.
• Create a user with only delete permission on this bucket:
  curl -X PUT http://localhost:8091/settings/rbac/users/builtin/deleter -d "name=Deleter&roles=data_reader_writer[closed2],query_delete[closed2]&password=pwdeleter" -u Administrator:password

• Using cbauth, authorize as deleter:pwdeleter, and request permission cluster.bucket[closed2].n1ql.insert!execute. This permission is granted, but should not be.

Unfortunately I don't have an end-to-end reproducer. The code in the query engine that asks for statement type permissions is currently commented out, since it would break access to open (no-password) buckets. Let me know if you need a specially-built query engine, and I'll provide one.

Ref: test case 6.b), 7.c)