None of the Victoria Metrics services should run as a dynamic user.
Indeed, enabling the setting appears to have no effect when `User` is
defined and refers to a user that already exists. To reduce confusion,
we should omit these directives from the unit files.
There's no reason for these to be separate packages. They come from the
same source tree, so having a single package makes more sense. I only
separated them originally because I wasn't sure exactly how to express
the proper options in the kconfig language.
