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/github_release.go

@@ -0,0 +1,26 @@
+// Copyright (c) 2015-present Mattermost, Inc. All Rights Reserved.
+// See LICENSE.txt for license information.
+
+package model
+
+import (
+	"net/http"
+)
+
+type GithubReleaseInfo struct {
+	Id          int    `json:"id"`
+	TagName     string `json:"tag_name"`
+	Name        string `json:"name"`
+	CreatedAt   string `json:"created_at"`
+	PublishedAt string `json:"published_at"`
+	Body        string `json:"body"`
+	Url         string `json:"html_url"`
+}
+
+func (g *GithubReleaseInfo) IsValid() *AppError {
+	if g.Id == 0 {
+		return NewAppError("GithubReleaseInfo.IsValid", NoTranslation, nil, "empty ID", http.StatusInternalServerError)
+	}
+
+	return nil
+}