Prevent to add PageInfo definition if not needed

[ooga]

Checklist

• Pull requests follows the contribution guide
• New or modified functionality is covered by tests

Description

Prevent RelayConnectionFactory to do extra work and add new definition when not needed.

[oryan-block]

Can you provide an example schema where this is a problem?
I'm not sure I understand what we're trying to solve here.

[vojtapol]

I believe the problem is that we are always adding some baked-in types to facilitate the relay @connection directive. If the users want to have their own type called PageInfo for whatever reason they can't because it clashes.

[vojtapol]

Thanks for the contribution!