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

compiler/testData/diagnostics/tests/smartCasts/kt10483.fir.kt

@@ -0,0 +1,17 @@
+interface A
+class B : A {
+    operator fun invoke() = this
+}
+
+class C : A
+
+operator fun C.invoke(): B = B()
+
+fun foo(arg: A): B? {
+    if (arg is B) return arg()
+
+    if (arg is C) return arg()
+
+    return null
+}
+