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

compiler/testData/diagnostics/tests/smartCasts/intersectionScope/propertiesConflict.fir.kt

@@ -0,0 +1,20 @@
+// !CHECK_TYPE
+
+interface A {
+    val foo: Any?
+}
+
+interface C: A {
+    override val foo: String
+}
+interface B: A {
+    override var foo: String?
+}
+
+fun test(a: A) {
+    if (a is B && a is C) {
+        a.<!AMBIGUITY!>foo<!> = ""
+        a.<!AMBIGUITY!>foo<!> = null
+        a.<!AMBIGUITY!>foo<!>
+    }
+}