Update gorilla/websockets library from 1.5.0 to latest 1.5.3

vendor/github.com/gorilla/websocket/client.go

@@ -9,6 +9,7 @@ import (
 	"context"
 	"crypto/tls"
 	"errors"
+	"fmt"
 	"io"
 	"io/ioutil"
 	"net"
@@ -318,14 +319,14 @@ func (d *Dialer) DialContext(ctx context.Context, urlStr string, requestHeader h
 	}
 
 	netConn, err := netDial("tcp", hostPort)
+	if err != nil {
+		return nil, nil, err
+	}
 	if trace != nil && trace.GotConn != nil {
 		trace.GotConn(httptrace.GotConnInfo{
 			Conn: netConn,
 		})
 	}
-	if err != nil {
-		return nil, nil, err
-	}
 
 	defer func() {
 		if netConn != nil {
@@ -370,6 +371,17 @@ func (d *Dialer) DialContext(ctx context.Context, urlStr string, requestHeader h
 
 	resp, err := http.ReadResponse(conn.br, req)
 	if err != nil {
+		if d.TLSClientConfig != nil {
+			for _, proto := range d.TLSClientConfig.NextProtos {
+				if proto != "http/1.1" {
+					return nil, nil, fmt.Errorf(
+						"websocket: protocol %q was given but is not supported;"+
+							"sharing tls.Config with net/http Transport can cause this error: %w",
+						proto, err,
+					)
+				}
+			}
+		}
 		return nil, nil, err
 	}