JoiningMigration: preserve comments in removed toString() call

java/java-tests/testData/codeInsight/daemonCodeAnalyzer/quickFix/streamApiMigration/joining/afterJoining.java

@@ -8,6 +8,7 @@ public class Test {
     String sb;
     System.out.println("hello");
       sb = list.stream().filter(s -> !s.isEmpty()).map(String::trim).collect(Collectors.joining());
-    return sb.length() == 0 ? null : sb;
+      //comment
+      return sb.length() == 0 ? null : sb;
   }
 }

java/java-tests/testData/codeInsight/daemonCodeAnalyzer/quickFix/streamApiMigration/joining/beforeJoining.java

@@ -11,6 +11,7 @@ public class Test {
         sb.append(s.trim());
       }
     }
-    return sb.length() == 0 ? null : sb.toString();
+    return sb.length() == 0 ? null : sb.toString//comment
+      ();
   }
 }