feat(graphql-rpc): Provide paginated response using transaction digests as the cursor for the `transactionBlocksByDigests`

[tomxey]

... I think it still makes sense that we provide paginated response using transaction digests as the cursor. This can be delegated to a new issue.

Originally posted by @kodemartin in #8990 (review)

[github-actions]

This issue is stale because it has been open 180 days with no activity.