Mono repo -> Master (#22553)

Combines the following repositories into one:

https://github.com/mattermost/mattermost-server
https://github.com/mattermost/mattermost-webapp
https://github.com/mattermost/focalboard
https://github.com/mattermost/mattermost-plugin-playbooks

server/platform/services/upgrader/upgrader.go

@@ -0,0 +1,18 @@
+// Copyright (c) 2015-present Mattermost, Inc. All Rights Reserved.
+// See LICENSE.txt for license information.
+//go:build !linux
+// +build !linux
+
+package upgrader
+
+func CanIUpgradeToE0() error {
+	return &InvalidArch{}
+}
+
+func UpgradeToE0() error {
+	return &InvalidArch{}
+}
+
+func UpgradeToE0Status() (int64, error) {
+	return 0, &InvalidArch{}
+}