Change .hashCode() to .bar() for some nullability fixes tests

Hash code can be no more used because in 1.3 we have nullable extension.
This fixes two wrap with safe let call tests and
one surround with null check test.

idea/testData/quickfix/wrapWithSafeLetCall/unstableValue.kt

@@ -1,13 +1,14 @@
 // "Wrap with '?.let { ... }' call" "false"
 // WITH_RUNTIME
 // ACTION: Add non-null asserted (!!) call
-// ACTION: Introduce local variable
 // ACTION: Replace with safe (?.) call
 // ERROR: Only safe (?.) or non-null asserted (!!.) calls are allowed on a nullable receiver of type Int?
 
+fun Int.bar() {}
+
 class My(var x: Int?) {
 
     fun foo() {
-        x<caret>.hashCode()
+        x<caret>.bar()
     }
 }