Create `install-dependencies` script about umbrel

[nioncode]

I'm not sure if I follow 100%, but will these dependencies be installed inside a docker container or on the host system itself?
I always liked the concept of umbrel that basically everything is defined in docker containers, which makes it easy to run umbrel on all sorts of devices and completely different distributions, since there are almost no requirements on the host system.

So imo it would be great if this philosophy would be kept and to not install random dependencies on the host through apt or other package managers, since not all hosts will use the same package manager.