[FIR-TEST] Add new testdata generated after changes in previous commit

compiler/testData/diagnostics/tests/smartCasts/safecalls/innerReceiver.fir.kt

@@ -0,0 +1,8 @@
+fun foo(x: String): String? = x
+
+fun calc(x: String?, y: String?): Int {
+    // Smart cast because of y!! in receiver
+    x?.subSequence(y!!.subSequence(0, 1).length, y.length)
+    // No smart cast possible
+    return y.<!INAPPLICABLE_CANDIDATE!>length<!>
+}