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/push_notification_test.go

@@ -0,0 +1,57 @@
+// 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 TestPushNotificationDeviceId(t *testing.T) {
+
+	msg := PushNotification{Platform: "test"}
+
+	msg.SetDeviceIdAndPlatform("android:12345")
+	require.Equal(t, msg.Platform, "android", msg.Platform)
+	require.Equal(t, msg.DeviceId, "12345", msg.DeviceId)
+	msg.Platform = ""
+	msg.DeviceId = ""
+
+	msg.SetDeviceIdAndPlatform("android:12:345")
+	require.Equal(t, msg.Platform, "android", msg.Platform)
+	require.Equal(t, msg.DeviceId, "12:345", msg.DeviceId)
+	msg.Platform = ""
+	msg.DeviceId = ""
+
+	msg.SetDeviceIdAndPlatform("android::12345")
+	require.Equal(t, msg.Platform, "android", msg.Platform)
+	require.Equal(t, msg.DeviceId, ":12345", msg.DeviceId)
+	msg.Platform = ""
+	msg.DeviceId = ""
+
+	msg.SetDeviceIdAndPlatform(":12345")
+	require.Equal(t, msg.Platform, "", msg.Platform)
+	require.Equal(t, msg.DeviceId, "12345", msg.DeviceId)
+	msg.Platform = ""
+	msg.DeviceId = ""
+
+	msg.SetDeviceIdAndPlatform("android:")
+	require.Equal(t, msg.Platform, "android", msg.Platform)
+	require.Equal(t, msg.DeviceId, "", msg.DeviceId)
+	msg.Platform = ""
+	msg.DeviceId = ""
+
+	msg.SetDeviceIdAndPlatform("")
+	require.Equal(t, msg.Platform, "", msg.Platform)
+	require.Equal(t, msg.DeviceId, "", msg.DeviceId)
+	msg.Platform = ""
+	msg.DeviceId = ""
+
+	msg.SetDeviceIdAndPlatform(":")
+	require.Equal(t, msg.Platform, "", msg.Platform)
+	require.Equal(t, msg.DeviceId, "", msg.DeviceId)
+	msg.Platform = ""
+	msg.DeviceId = ""
+}