Remove warning for metadataBase fallback (#48196)
[slack
thread](https://vercel.slack.com/archives/C03KAR5DCKC/p1681079578508909)
Remove the warning for metadataBase when it fallback to default value,
as it's already clarified in
[docs](https://beta.nextjs.org/docs/api-reference/metadata#metadatabase)
