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/oauth_test.go

@@ -0,0 +1,70 @@
+// Copyright (c) 2015-present Mattermost, Inc. All Rights Reserved.
+// See LICENSE.txt for license information.
+
+package model
+
+import (
+	"testing"
+
+	"github.com/stretchr/testify/require"
+)
+
+func TestOAuthAppPreSave(t *testing.T) {
+	a1 := OAuthApp{}
+	a1.Id = NewId()
+	a1.Name = "TestOAuthApp" + NewId()
+	a1.CallbackUrls = []string{"https://nowhere.com"}
+	a1.Homepage = "https://nowhere.com"
+	a1.IconURL = "https://nowhere.com/icon_image.png"
+	a1.ClientSecret = NewId()
+	a1.PreSave()
+	a1.Etag()
+	a1.Sanitize()
+}
+
+func TestOAuthAppPreUpdate(t *testing.T) {
+	a1 := OAuthApp{}
+	a1.Id = NewId()
+	a1.Name = "TestOAuthApp" + NewId()
+	a1.CallbackUrls = []string{"https://nowhere.com"}
+	a1.Homepage = "https://nowhere.com"
+	a1.IconURL = "https://nowhere.com/icon_image.png"
+	a1.ClientSecret = NewId()
+	a1.PreUpdate()
+}
+
+func TestOAuthAppIsValid(t *testing.T) {
+	app := OAuthApp{}
+
+	require.NotNil(t, app.IsValid())
+
+	app.Id = NewId()
+	require.NotNil(t, app.IsValid())
+
+	app.CreateAt = 1
+	require.NotNil(t, app.IsValid())
+
+	app.UpdateAt = 1
+	require.NotNil(t, app.IsValid())
+
+	app.CreatorId = NewId()
+	require.NotNil(t, app.IsValid())
+
+	app.ClientSecret = NewId()
+	require.NotNil(t, app.IsValid())
+
+	app.Name = "TestOAuthApp"
+	require.NotNil(t, app.IsValid())
+
+	app.CallbackUrls = []string{"https://nowhere.com"}
+	require.NotNil(t, app.IsValid())
+
+	app.MattermostAppID = "Some app ID"
+	require.NotNil(t, app.IsValid())
+
+	app.Homepage = "https://nowhere.com"
+	require.Nil(t, app.IsValid())
+
+	app.IconURL = "https://nowhere.com/icon_image.png"
+	require.Nil(t, app.IsValid())
+}