Fix: Move WS error handling (#174)

Moves all WS handling of unexpected payloads into the stream to prevent code duplication.

This also prevents non-{Hello,Resumed,Ready} messages from causing a handshake failure, as it seems Discord do not prevent such messages from appearing.

---------

Co-authored-by: Kyle Simpson <kyleandrew.simpson@gmail.com>

src/driver/connection/mod.rs

@@ -95,8 +95,6 @@ impl Connection {
                 },
                 other => {
                     debug!("Expected ready/hello; got: {:?}", other);
-
-                    return Err(Error::ExpectedHandshake);
                 },
             }
         }
@@ -304,8 +302,6 @@ impl Connection {
                 },
                 other => {
                     debug!("Expected resumed/hello; got: {:?}", other);
-
-                    return Err(Error::ExpectedHandshake);
                 },
             }
         }