Create From Usage: Move "Create function"-related tests to separate directory

idea/testData/quickfix/createFromUsage/createFunction/call/beforeThisInNestedClass2.kt

@@ -0,0 +1,9 @@
+// "Create function 'foo' from usage" "true"
+
+class A<T>(val n: T) {
+    inner class B<U>(val m: U) {
+        fun test(): A<Int> {
+            return this@A.<caret>foo(2, "2")
+        }
+    }
+}