doc(cloudflare): update type generation command

[Stradi]

This PR updates following:

1. We are not using --experimental-include-runtime anymore, since Wrangler now generates runtime types too. When running wrangler types with the flag above, CLI shows an error and stops generating types;

✘ [ERROR] You no longer need to use --experimental-include-runtime.

  `wrangler types` will now generate runtime types in the same file as the Env types.
  You should delete the old runtime types file, and remove it from your tsconfig.json.
  Then rerun `wrangler types`.

2. Include --env-interface flag. This ensures that getCloudflareContext() returns correct binding types. OpenNext has CloudflareEnv interface but by default Wrangler saves bindings in Env interface. This causes CloudflareEnv (used by OpenNext) not have the correct types for bindings.

Some issues I've found about this:

• fixes [BUG] Bindings types aren't being populated despite running npx wrangler types opennextjs-cloudflare#597
• [BUG] TypeScript Binding Generation doesn't work opennextjs-cloudflare#238

[james-elicx]

thanks!