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

compiler/testData/diagnostics/tests/smartCasts/variables/whileWithBreak.fir.kt

@@ -0,0 +1,17 @@
+fun String.next(): String {
+    return "abc"
+}
+
+fun list(start: String) {
+    var e: Any? = start
+    if (e==null) return
+    while (e is String) {
+        // Smart cast due to the loop condition
+        if (e.length == 0)
+            break
+        // We still have smart cast here despite of a break
+        e = e.next()
+    }
+    // e can never be null but we do not know it
+    e.hashCode()
+}