@nx/react - express as optional dependency

[karlismelderis-mckinsey]

Can we please try to reduce amount of dependencies installed 🙏

express us used in generators and would not be needed in day to day work (not to mention in CI run when we install NX just to run lint, test and other build tasks)

but unfortunately NX is pulling in everything that it might possibly need

It would be really nice to reduce packages NX installs by default and dev can cherry-pick anything else it need when one time case arrives