[#2333] Improvement: extend the timeout value for QuorumTest#case6 (#2348)

### What changes were proposed in this pull request?
extend the timeout value for QuorumTest#case6

### Why are the changes needed?
Fix: #2333 

### Does this PR introduce _any_ user-facing change?
No.

### How was this patch tested?
current UT

Author: cchung100m

integration-test/common/src/test/java/org/apache/uniffle/test/QuorumTest.java

@@ -378,7 +378,7 @@ public void case1() throws Exception {
     registerShuffleServer(testAppId, 3, 2, 2, true);
     Roaring64NavigableMap blockIdBitmap = Roaring64NavigableMap.bitmapOf();
 
-    // only 1 server is timout, the block sending should success
+    // only 1 server is timeout, the block sending should success
     enableTimeout((MockedShuffleServer) grpcShuffleServers.get(2), 500);
 
     // report result should success
@@ -719,9 +719,9 @@ public void case6() throws Exception {
             expectedData,
             Lists.newArrayList(shuffleServerInfo2, shuffleServerInfo3, shuffleServerInfo4));
 
-    // server 0,1,2 are ok, server 3,4 are timout
-    enableTimeout((MockedShuffleServer) grpcShuffleServers.get(3), 500);
-    enableTimeout((MockedShuffleServer) grpcShuffleServers.get(4), 500);
+    // server 0,1,2 are ok, server 3,4 are timeout
+    enableTimeout((MockedShuffleServer) grpcShuffleServers.get(3), 2000);
+    enableTimeout((MockedShuffleServer) grpcShuffleServers.get(4), 2000);
 
     Map<Integer, Set<Long>> partitionToBlockIds = Maps.newHashMap();
     partitionToBlockIds.put(0, Sets.newHashSet(blockIdBitmap0.stream().iterator()));