Well that’s great news ! Please do not hesitate to report as you’ll be my first beta tester of “magisk google app” suite that I know of 
Be aware that this is a rather peculiar way to get Gapps working as it depends on Magisk system partition. This means that the moment you lose root capabilities, your entire Google Suite will be “disabled” as well as the applications that rely on it.
Even though I “think” it would be just a matter of rerooting the device if you ever lost root, I wouldn’t be surprised if it led to some issues.
Therefore, be careful to follow the root retention procedure for OTA updates using Magisk 
On the bright side, your phone is not “really” googlized as you can get rid of everything and get a perfectly clean phone by simply disabling root/disabling the module, which is a luxury !