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

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

@@ -0,0 +1,13 @@
+// !DIAGNOSTICS: -UNUSED_PARAMETER
+fun foo(arg: Int?) {
+    var x = arg
+    if (x == null) return
+    run {
+        // Unsafe because of owner modification
+        x.hashCode()
+        x = null
+    }
+    if (x != null) x = 42
+    // Unsafe because of lambda
+    x.<!UNRESOLVED_REFERENCE!>hashCode<!>()
+}