Find a way to streamline commandline options

[Breee]

What problem are you facing?

The commandline Arguments we can pass to providers are inconsistent across the different providers out there.

https://github.com/upbound/upjet-provider-template/blob/main/cmd/provider/main.go#L36
vs https://github.com/upbound/provider-gcp/blob/main/cmd/provider/appengine/zz_main.go#L54
vs https://github.com/upbound/provider-terraform/blob/main/cmd/provider/main.go#L50

It would be nice if we could generalize and streamline the way to get the current set of commandline options easily into the generated providers