do not need parenthesis for associative operations (IDEADEV-41569); move to java-tests

java/java-tests/testData/refactoring/introduceVariable/SCR18295.after.java

@@ -0,0 +1,9 @@
+public class Thing {
+
+    private String it;
+
+    private void dumb() {
+        String it = this.it;
+        it.length();
+    }
+}