KT-11104 extra : name validator introduced for wrap with safe let call

idea/testData/quickfix/wrapWithSafeLetCall/insideLet.kt

@@ -0,0 +1,8 @@
+// "Wrap with '?.let { ... }' call" "true"
+// WITH_RUNTIME
+
+fun foo(x: String?, y: String) {
+    y.let { bar(<caret>x, it) }
+}
+
+fun bar(s: String, t: String) = s.hashCode() + t.hashCode()