fix(e2e): add admin fixture to global setup

The permission-redirect.spec.ts tests use authFixtures.admin,
but the global setup was not generating admin.local.json.

This caused all Admin role tests to fail in CI with:
'ENOENT: no such file or directory, open e2e/fixtures/auth/admin.local.json'

Author: zainfathoni

playwright-global-setup.ts

@@ -42,6 +42,9 @@ async function globalSetup() {
   // course author
   await loginAs(browser, 'author')
 
+  // admin
+  await loginAs(browser, 'admin')
+
   await browser.close()
 }