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

compiler/testData/diagnostics/tests/cast/IsErasedUpcastToNonReified.fir.kt

@@ -0,0 +1,27 @@
+fun <T, S : T> test(x: T?, y: S, z: T) {
+    x is T
+    x is T?
+
+    y is T
+    y is S
+    y is T?
+    y is S?
+
+    z is T
+    z is T?
+
+    null as T
+    null as T?
+    null as S
+}
+
+inline fun <reified T> test(x: T?) {
+    x is T
+    null as T
+    null as T?
+}
+
+fun <T> foo(x: List<T>, y: List<T>?) {
+    x is List<T>
+    y is List<T>
+}