add base override for runtime status to install specs

src/Umbraco.Web.UI.Client/e2e/installer.spec.ts

@@ -0,0 +1,26 @@
+import { rest } from 'msw';
+
+import umbracoPath from '../src/core/helpers/umbraco-path';
+import { StatusResponse } from '../src/core/models';
+import { expect, test } from '../test';
+
+test('installer is shown', async ({ page, worker }) => {
+	await worker.use(
+		// Override the server status to be "must-install"
+		rest.get(umbracoPath('/server/status'), (_req, res, ctx) => {
+			return res(
+				// Respond with a 200 status code
+				ctx.status(200),
+				ctx.json<StatusResponse>({
+					serverStatus: 'must-install',
+				})
+			);
+		})
+	);
+
+	await page.goto('/install');
+
+	await page.waitForSelector('[data-test="installer"]');
+
+	await expect(page).toHaveURL('/install');
+});