In App.samplingNavigation.test.tsx, (#1035)

- replaced test for Reject button with the one used in the regular sampling test, which gets the button by role. This test appeared to be failing because formatting puts the name between the button elements with some whitespace. The way to look is with a regex

client/src/__tests__/App.samplingNavigation.test.tsx

@@ -229,7 +229,7 @@ describe("App - Sampling auto-navigation", () => {
       expect(screen.getByTestId("sampling-request")).toBeTruthy();
     });
 
-    fireEvent.click(screen.getByText("Reject"));
+    fireEvent.click(screen.getByRole("button", { name: /Reject/i }));
 
     await waitFor(() => {
       expect(reject).toHaveBeenCalled();