Add Maintainerr as an application in the control panel

Full disclosure, I haven't used the app but it really looks like I'd like to. Seems like it would be a great fit for the service. I especially like the feature where it can remove moves and tv shows and reset the request status in Overseerr. Right now I use a python script to automatically delete media after it reaches a certain age but this seems like it would offer a lot more configurability. Unfortunately, the repo only offers docker images or I'd install it over SSH myself.