Connector: Handle +1000 stakes for proposal queries

[fabriziovigevani]

The graph only lets you to query up to 1000 entities per query, so when querying for a proposal, we need to handle pagination for proposals that have more than 1000 active stakes.

[0xGabi]

We need to update the connector.

[reznord]

Look at examples on how to implement cursors (for pagination) in subgraph.

Link: https://graphql.org/learn/pagination/#pagination-and-edges