Do not strip loader arg in dynamic for server components (#42426)
When `ssr: false` option is presented, we stripped the loader option for
`next/dynamic` call. But for react server components (both server and
client ones) we're using a `React.lazy` based implementation so we
shouldn't do it for them.
## Bug
- [ ] Related issues linked using `fixes #number`
- [x] Integration tests added
- [ ] Errors have a helpful link attached, see `contributing.md`