Merge pull request #5283 from 317787106/hotfix/block_chain_failed

fix(net):prefer to get blockId from khaosdb in SyncService

Author: 317787106

framework/src/main/java/org/tron/core/net/service/sync/SyncService.java

@@ -209,7 +209,11 @@ private LinkedList<BlockId> getBlockChainSummary(PeerConnection peer) throws P2p
   }
 
   private BlockId getBlockIdByNum(long num) throws P2pException {
-    BlockId head = tronNetDelegate.getHeadBlockId();
+    BlockId head = tronNetDelegate.getKhaosDbHeadBlockId();
+    if (num == head.getNum()) {
+      return head;
+    }
+    head = tronNetDelegate.getHeadBlockId();
     if (num == head.getNum()) {
       return head;
     }