[enhancement](Nereids): when rule return original plan, skip copyIn() (#25730)

fe/fe-core/src/test/java/org/apache/doris/nereids/sqltest/CascadesJoinReorderTest.java

@@ -33,7 +33,7 @@ import org.junit.jupiter.api.Test;
  *   bushy: star graph can't be a bushy, it can only form a zig-zag (because the center must be joined first)
  * </pre>
  */
-public class CascadesJoinReorderTest extends SqlTestBase {
+class CascadesJoinReorderTest extends SqlTestBase {
     @Test
     void testStartThreeJoin() {
         // Three join