[#5172]fix bug:Iceberg catalog audit user is not correct (#5208)

### What changes were proposed in this pull request?

Iceberg and JDBC catalog audit user is not correct

### Why are the changes needed?

Fix: #5172 

### Does this PR introduce _any_ user-facing change?

No

### How was this patch tested?

No need

catalogs/catalog-jdbc-common/src/main/java/org/apache/gravitino/catalog/jdbc/JdbcCatalogOperations.java

@@ -74,6 +74,7 @@
 import org.apache.gravitino.rel.indexes.Index;
 import org.apache.gravitino.utils.IsolatedClassLoader;
 import org.apache.gravitino.utils.MapUtils;
+import org.apache.gravitino.utils.PrincipalUtils;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 
@@ -570,9 +571,8 @@ private TableChange[] replaceJdbcProperties(TableChange[] changes) {
         .toArray(TableChange[]::new);
   }
 
-  // TODO. We should figure out a better way to get the current user from servlet container.
   private static String currentUser() {
-    return System.getProperty("user.name");
+    return PrincipalUtils.getCurrentUserName();
   }
 
   public void deregisterDriver(Driver driver) throws SQLException {

catalogs/catalog-lakehouse-iceberg/src/main/java/org/apache/gravitino/catalog/lakehouse/iceberg/IcebergCatalogOperations.java

@@ -62,6 +62,7 @@
 import org.apache.gravitino.rel.expressions.transforms.Transform;
 import org.apache.gravitino.rel.indexes.Index;
 import org.apache.gravitino.utils.MapUtils;
+import org.apache.gravitino.utils.PrincipalUtils;
 import org.apache.iceberg.catalog.TableIdentifier;
 import org.apache.iceberg.exceptions.AlreadyExistsException;
 import org.apache.iceberg.exceptions.NamespaceNotEmptyException;
@@ -587,8 +588,7 @@ public void testConnection(
     }
   }
 
-  // TODO. We should figure out a better way to get the current user from servlet container.
   private static String currentUser() {
-    return System.getProperty("user.name");
+    return PrincipalUtils.getCurrentUserName();
   }
 }