[Test] Add a test covering changes in the evaluation semantics of safe call with smart cast in K2

Addition to other safe call tests that are already present in tests.

^KT-41034

compiler/testData/diagnostics/tests/safeCalls/safeCallWithSmartCast.kt

@@ -0,0 +1,15 @@
+// WITH_STDLIB
+
+class C {
+    var x: Int = 0
+}
+
+fun test(с: C?, a: Any) {
+    с?.x = if (a is String) 0 else throw Exception();
+    <!DEBUG_INFO_SMARTCAST!>a<!>.<!DEPRECATION!>toUpperCase<!>()
+}
+
+
+fun main(args: Array<String>) {
+    test(null, 1)
+}