Revert "E2E disable Cypress retries"

This reverts commit 97b058f7.

alfa-client/apps/alfa-e2e/cypress.config.ts

@@ -12,4 +12,13 @@ export default defineConfig({
       return cypressEvents(on, config);
     },
   },
+  retries: {
+    experimentalStrategy: 'detect-flake-and-pass-on-threshold',
+    experimentalOptions: {
+      maxRetries: 2,
+      passesRequired: 1,
+    },
+    openMode: true,
+    runMode: true,
+  },
 });