v8.0 module release (#22975)

https://mattermost.atlassian.net/browse/MM-52079

```release-note
We upgrade the module version to 8.0. The new module path is github.com/mattermost-server/server/v8.
```


Co-authored-by: Doug Lauder <wiggin77@warpmail.net>

server/model/command_webhook.go

@@ -0,0 +1,60 @@
+// Copyright (c) 2015-present Mattermost, Inc. All Rights Reserved.
+// See LICENSE.txt for license information.
+
+package model
+
+import (
+	"net/http"
+)
+
+type CommandWebhook struct {
+	Id        string
+	CreateAt  int64
+	CommandId string
+	UserId    string
+	ChannelId string
+	RootId    string
+	UseCount  int
+}
+
+const (
+	CommandWebhookLifetime = 1000 * 60 * 30
+)
+
+func (o *CommandWebhook) PreSave() {
+	if o.Id == "" {
+		o.Id = NewId()
+	}
+
+	if o.CreateAt == 0 {
+		o.CreateAt = GetMillis()
+	}
+}
+
+func (o *CommandWebhook) IsValid() *AppError {
+	if !IsValidId(o.Id) {
+		return NewAppError("CommandWebhook.IsValid", "model.command_hook.id.app_error", nil, "", http.StatusBadRequest)
+	}
+
+	if o.CreateAt == 0 {
+		return NewAppError("CommandWebhook.IsValid", "model.command_hook.create_at.app_error", nil, "id="+o.Id, http.StatusBadRequest)
+	}
+
+	if !IsValidId(o.CommandId) {
+		return NewAppError("CommandWebhook.IsValid", "model.command_hook.command_id.app_error", nil, "", http.StatusBadRequest)
+	}
+
+	if !IsValidId(o.UserId) {
+		return NewAppError("CommandWebhook.IsValid", "model.command_hook.user_id.app_error", nil, "", http.StatusBadRequest)
+	}
+
+	if !IsValidId(o.ChannelId) {
+		return NewAppError("CommandWebhook.IsValid", "model.command_hook.channel_id.app_error", nil, "", http.StatusBadRequest)
+	}
+
+	if o.RootId != "" && !IsValidId(o.RootId) {
+		return NewAppError("CommandWebhook.IsValid", "model.command_hook.root_id.app_error", nil, "", http.StatusBadRequest)
+	}
+
+	return nil
+}