docs(subscriber): fix typo in doc comment

[joshka]

error[E0433]: failed to resolve: use of undeclared crate or module `tower_web`
 --> console-subscriber/src/lib.rs:989:5
  |
9 | use tower_web::cors::{CorsLayer, AllowOrigin};
  |     ^^^^^^^^^ use of undeclared crate or module `tower_web`
  |
help: there is a crate or module with a similar name
  |
9 | use tonic_web::cors::{CorsLayer, AllowOrigin};

The actual struct is https://docs.rs/tower-http/latest/tower_http/cors/struct.CorsLayer.html

[hds]

Thank you very much!