ubuntu-drivers should not run unless user is root

[Jeff Lane ]

one cannot install drivers unless one is root (or has root priv escalation via sudo).

For that reason, ubuntu-drivers should not run without a priv check.

ubuntu@doubletusk:~$ ubuntu-drivers --gpgpu autoinstall
This is gpgpu mode
E: Could not open lock file /var/lib/dpkg/lock-frontend - open (13: Permission denied)
E: Unable to acquire the dpkg frontend lock (/var/lib/dpkg/lock-frontend), are you root?

This shouldn't trigger the apt privilege error, ubuntu-drivers itself should check to see if it's running as root and then prompt the user.

[Jeff Lane  (bladernr)]

Even uglier traceback when trying to directly install the nvidia 470 server driver without using sudo:

ubuntu@polari:~$ ubuntu-drivers --gpgpu install nvidia:470-server
This is gpgpu mode
Traceback (most recent call last):
  File "/usr/bin/ubuntu-drivers", line 487, in <module>
    greet()
  File "/usr/lib/python3/dist-packages/click/core.py", line 722, in __call__
    return self.main(*args, **kwargs)
  File "/usr/lib/python3/dist-packages/click/core.py", line 697, in main
    rv = self.invoke(ctx)
  File "/usr/lib/python3/dist-packages/click/core.py", line 1066, in invoke
    return _process_result(sub_ctx.command.invoke(sub_ctx))
  File "/usr/lib/python3/dist-packages/click/core.py", line 895, in invoke
    return ctx.invoke(self.callback, **ctx.params)
  File "/usr/lib/python3/dist-packages/click/core.py", line 535, in invoke
    return callback(*args, **kwargs)
  File "/usr/lib/python3/dist-packages/click/decorators.py", line 64, in new_func
    return ctx.invoke(f, obj, *args[1:], **kwargs) ...