fix(e2e): remove unused isStaging function and update tests

- Removed the unused `isStaging` function from `utils.ts`.
- Replaced `isStaging` with `isProduction` in landings spec tests.
- Updated test skipping logic for reverse-proxy hosts.

Author: zoobestik

test/production/landings.spec.ts

@@ -1,10 +1,10 @@
-import { test, expect } from '@playwright/test';
-import { isStaging } from '../utils';
+import { expect, test } from '@playwright/test';
+import { isProduction } from '../utils';
 
 test.describe('/lp/ pages list', async () => {
-    test(`Check /lp/multiplatform default redirects`, async ({ page, baseURL }) => {
-        test.skip(isStaging(baseURL), 'for host with reverse-proxy only');
+    test.skip(({ baseURL }) => isProduction(baseURL), 'for host with reverse-proxy only');
 
+    test(`Check /lp/multiplatform default redirects`, async ({ page, baseURL }) => {
         const targetUrl = 'https://kotlinlang.org/multiplatform/';
 
         await page.goto('/lp/multiplatform');
@@ -18,7 +18,6 @@ test.describe('/lp/ pages list', async () => {
     });
 
     test(`Check /lp/multiplatform case-studies redirect`, async ({ page, baseURL }) => {
-        test.skip(isStaging(baseURL), 'for host with reverse-proxy only');
         const targetUrl = 'https://kotlinlang.org/case-studies/?type=multiplatform';
 
         await page.goto('/lp/multiplatform/case-studies/');

test/utils.ts

@@ -3,11 +3,6 @@ import { PageAssertionsToHaveScreenshotOptions } from 'playwright/types/test';
 
 export const testSelector = (name: string) => `[data-test="${name}"]`;
 
-export function isStaging(baseURL: string): boolean {
-    const { hostname } = new URL(baseURL);
-    return hostname !== 'kotlinlang.org';
-}
-
 const TRANSITION_TIMEOUT = 2000;
 
 export async function checkAnchor(page: Page, anchor: Locator) {