node tests: Clear state in narrow_unread test.

frontend_tests/node_tests/narrow_unread.js

@@ -42,6 +42,9 @@ function candidate_ids() {
 }
 
 run_test("get_unread_ids", () => {
+    unread.declare_bankruptcy();
+    narrow_state.reset_current_filter();
+
     let unread_ids;
     let terms;