[Enhancement] Optimize IdChain hash code implement (#47599)

The current implement of hashCode is easy to cause conflict. The data in the attachment takes 15 minutes to construct a HashMap<IdChain, IdChain> using the current hashCode implementation, but only takes a few seconds after changing to Arrays.hashCode().


[chain.json.tar.gz](https://github.com/user-attachments/files/16014242/chain.json.tar.gz)


Signed-off-by: gengjun-git <gengjun@starrocks.com>

fe/fe-core/src/main/java/com/starrocks/backup/RestoreFileMapping.java

@@ -43,6 +43,7 @@
 import java.io.DataInput;
 import java.io.DataOutput;
 import java.io.IOException;
+import java.util.Arrays;
 import java.util.Map;
 
 public class RestoreFileMapping implements Writable {
@@ -109,11 +110,7 @@ public boolean equals(Object obj) {
 
         @Override
         public int hashCode() {
-            int code = chain[0].hashCode();
-            for (int i = 1; i < 5; i++) {
-                code ^= chain[i].hashCode();
-            }
-            return code;
+            return Arrays.hashCode(chain);
         }
 
         @Override