Fetch event logs for a block range in a single upstream call (#433)

* Support fetching logs for a block range in rpc-eth-client

* Add a method to fetch block events for multiple blocks at once

* Add a method to save blocks with fetched events in a block range

* Fix transactions destructuring

* Fix get logs call args

* Add a separate ETH client method to get logs in a block range

* Codegen changes

packages/graph-node/test/utils/indexer.ts

@@ -106,6 +106,12 @@ export class Indexer implements IndexerInterface {
     return '';
   }
 
+  async fetchEventsAndSaveBlocks (blocks: DeepPartial<BlockProgressInterface>[]): Promise<{ blockProgress: BlockProgressInterface, events: DeepPartial<EventInterface>[] }[]> {
+    assert(blocks);
+
+    return [];
+  }
+
   async saveBlockAndFetchEvents (block: BlockProgressInterface): Promise<[BlockProgressInterface, DeepPartial<EventInterface>[]]> {
     return [block, []];
   }