add test cases

test/repositories/UnoptimizedInMemoryRepositoryTests.test.ts

@@ -226,11 +226,15 @@ describe("UnoptimizedInMemoryRepository", () => {
   });
 
   describe("subscribeToEtaChanges", () => {
-    test("notifies listener if the eta has changed")
+    test("notifies listeners if etas has changed", async () => {
+
+    });
   });
 
   describe("unsubscribeFromEtaChanges", () => {
+    test("stops notifying listeners after etas have stopped changing", async () => {
 
+    });
   });
 
   describe("getOrderedStopByRouteAndStopId", () => {