x/net/websocket: remove Gorilla recommendation in docs

[percybolmer]

What version of Go are you using (go version)?

1.18

Does this issue reproduce with the latest release?

No Issue

What operating system and processor architecture are you using (go env)?

What did you do?

Read the docs

What did you expect to see?

How to use the x/net/websocket library

What did you see instead?

https://github.com/golang/net/blob/e1ec361d0b39748d321472b2be7298211e05a3b6/websocket/websocket.go#L11
Gorilla recommendation which is now archived

[seankhliao]

archived: https://github.com/gorilla/websocket

cc @neild @ianlancetaylor

[gopherbot]

Change https://go.dev/cl/457356 mentions this issue: websocket: don't recommend Gorilla