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

compiler/testData/diagnostics/testsWithStdLib/smartcasts/lazyDeclaresAndModifies.fir.kt

@@ -0,0 +1,11 @@
+class My(val x: Int?) {
+    val y: Int? by lazy {
+        var z = x
+        while (z != null) {
+            z = z.hashCode()
+            if (z < 0) return@lazy z
+            if (z == 0) z = null
+        }
+        return@lazy null
+    }
+}