Fix flaky whitelabel test (#40441)

* Fix flaky whitelabel test

* Update another test for `landing-page`

e2e/test/scenarios/admin-2/whitelabel.cy.spec.js

@@ -327,7 +327,7 @@ describeEE("formatting > whitelabel", () => {
         .clear()
         .type("/test-1")
         .blur();
-      cy.wait(["@putLandingPage", "@getSettings"]);
+      undoToast().findByText("Changes saved").should("be.visible");
 
       cy.findByTestId("landing-page-error").should("not.exist");
       cy.findByRole("navigation").findByText("Exit admin").click();
@@ -340,7 +340,7 @@ describeEE("formatting > whitelabel", () => {
         .clear()
         .type("/test-2")
         .blur();
-      cy.wait(["@putLandingPage", "@getSettings"]);
+      undoToast().findByText("Changes saved").should("be.visible");
 
       // set to valid value then test invalid value is not persisted
       cy.findByLabelText("Landing page custom destination")

enterprise/frontend/src/metabase-enterprise/whitelabel/components/LandingPageWidget/LandingPageWidget.tsx

@@ -9,13 +9,10 @@ import { getRelativeLandingPageUrl } from "./utils";
 
 interface Props {
   settingValues: EnterpriseSettings;
-  onChangeSetting: (
-    key: "landing-page",
-    value: EnterpriseSettings["landing-page"],
-  ) => Promise<void>;
+  onChange: (value: EnterpriseSettings["landing-page"]) => Promise<void>;
 }
 
-export function LandingPageWidget({ onChangeSetting, settingValues }: Props) {
+export function LandingPageWidget({ onChange, settingValues }: Props) {
   const [error, setError] = useState<string | null>(null);
 
   const normalize = (value: string | number | null) => {
@@ -33,7 +30,7 @@ export function LandingPageWidget({ onChangeSetting, settingValues }: Props) {
     } else {
       setError(null);
       try {
-        await onChangeSetting("landing-page", relativeUrl);
+        await onChange(relativeUrl);
       } catch (e: any) {
         setError(e?.data?.message || t`Something went wrong`);
       }