fix(types): websocketPlugin is not an existing variable

[Yovach]

This PR fixes a mistake in types. The named exports websocketPlugin doesn't exist in the code and you can't use it

Until this PR is merged, you can do the following :

fastify-websocket.d.ts

import type websocketPlugin from "@fastify/websocket";

declare module "@fastify/websocket" {
  export const fastifyWebsocket: typeof websocketPlugin;
}

Checklist

• [ ] run npm run test and npm run benchmark
• [ ] tests and/or benchmarks are included
• [ ] documentation is changed or added
• [x] commit message and code follows the Developer's Certification of Origin and the Code of conduct

[Uzlopak]

Shame!

thank you.

[mcollina]

Can you add a test using tsd to prevent this for regressing?

[Yovach]

Can you add a test using tsd to prevent this for regressing?

I added a test for named-import but tests seems broken in fastify@4.24.0

[Uzlopak]

Other typings fails are unrelated to this PR.