Add request param to didEncounter method

[kamila-brylewska-zendesk]

Hello :)
I want to provide more information to didEncounterError method in RemoteGraphQLDataSource class.

During implementation of didEncounterError I noticed I didn't have enough information about subgraph request. As far as I know context is the same for all subgraph requests. Adding parameter request (type GatewayGraphQLRequest) would allow me to get more information about request with error.

this.didEncounterError(error, fetchRequest, fetchResponse, context, request);

I prepared PR to show you my idea more clearly. Thank you in advance!

[kamila-brylewska-zendesk]

My PR: #3194