Add better quickfix for scope functions #KT-13676 Fixed

idea/testData/quickfix/replaceWithSafeCallForScopeFunction/letWithWrongImplicitThis.kt

@@ -0,0 +1,13 @@
+// "Replace scope function with safe (?.) call" "false"
+// WITH_RUNTIME
+// ACTION: Add non-null asserted (!!) call
+// ACTION: Introduce local variable
+// ACTION: Move lambda argument into parentheses
+// ACTION: Replace with safe (this?.) call
+// ERROR: Only safe (?.) or non-null asserted (!!.) calls are allowed on a nullable receiver of type String?
+
+fun String?.foo(a: String?) {
+    a.let { s ->
+        <caret>length
+    }
+}