fix: set withdrawals properly when fetching empty block (#2386)

eth/fetcher/block_fetcher.go

@@ -639,6 +639,9 @@ func (f *BlockFetcher) loop() {
 							log.Trace("Block empty, skipping body retrieval", "peer", announce.origin, "number", header.Number, "hash", header.Hash())
 
 							block := types.NewBlockWithHeader(header)
+							if block.Header().EmptyWithdrawalsHash() {
+								block = block.WithWithdrawals(make([]*types.Withdrawal, 0))
+							}
 							block.ReceivedAt = task.time
 
 							complete = append(complete, block)

eth/protocols/eth/handlers.go

@@ -366,7 +366,6 @@ func handleBlockBodies(backend Backend, msg Decoder, peer *Peer) error {
 		for i, body := range res.BlockBodiesResponse {
 			txsHashes[i] = types.DeriveSha(types.Transactions(body.Transactions), hasher)
 			uncleHashes[i] = types.CalcUncleHash(body.Uncles)
-			// Withdrawals may be not nil, but a empty value when Sidecars not empty
 			if body.Withdrawals != nil {
 				withdrawalHashes[i] = types.DeriveSha(types.Withdrawals(body.Withdrawals), hasher)
 			}