Use mod vendor for vendored directory (backwards compatible)

vendor/github.com/mattermost/mattermost-server/model/websocket_request.go

@@ -1,34 +0,0 @@
-// Copyright (c) 2016-present Mattermost, Inc. All Rights Reserved.
-// See License.txt for license information.
-
-package model
-
-import (
-	"encoding/json"
-	"io"
-
-	goi18n "github.com/nicksnyder/go-i18n/i18n"
-)
-
-type WebSocketRequest struct {
-	// Client-provided fields
-	Seq    int64                  `json:"seq"`
-	Action string                 `json:"action"`
-	Data   map[string]interface{} `json:"data"`
-
-	// Server-provided fields
-	Session Session              `json:"-"`
-	T       goi18n.TranslateFunc `json:"-"`
-	Locale  string               `json:"-"`
-}
-
-func (o *WebSocketRequest) ToJson() string {
-	b, _ := json.Marshal(o)
-	return string(b)
-}
-
-func WebSocketRequestFromJson(data io.Reader) *WebSocketRequest {
-	var o *WebSocketRequest
-	json.NewDecoder(data).Decode(&o)
-	return o
-}