clean up onClick test

client/src/tests/GuessPane.test.js

@@ -50,7 +50,7 @@ describe("GuessPane", () => {
     });
     // check submit enabled
     expect(handle).toMatchSnapshot();
-    await handle.find("button").first().prop("onClick")();
+    await handle.find("button").first().simulate("click");
     expect(reverseGeocode).toHaveBeenCalledWith(
       expect.objectContaining({ lat: "lat", lng: "lng" })
     );