This pull request updates the environment variable configuration for
Okta metadata URLs in the `dogfood-gitops` GitHub Actions workflow.
Instead of using a single metadata URL, the workflow now distinguishes
between admin and end user metadata URLs.
Workflow configuration changes:
* Split the `DOGFOOD_OKTA_METADATA_URL` environment variable into two
separate variables: `DOGFOOD_OKTA_METADATA_URL_ADMINS` and
`DOGFOOD_OKTA_METADATA_URL_END_USERS` in the
`.github/workflows/dogfood-gitops.yml` workflow file.