interfaces/network-control: remove incorrect rules for tun

[jdstrand]

We had two udev rules to tag tun: tun and tun[0-9]*. This results in
'udev_enumerate_scan failed' errors. This is because udev ships this rule

KERNEL=="tun", MODE="0666", OPTIONS+="static_node=net/tun"

so we don't need the tun[0-9]* or tap[0-9]* rules. Removing it resolves the issue. This PR is safe because tun[0-9]* and tap[0-9]* are virtual devices (like other network devices) and aren't represented in /dev, and therefore don't need to be added to the device cgroup and therefore don't need to be udev tagged.

This PR also revert 65b7ef7 to remove the unneeded apparmor rules (the devices don't show up in /dev-- these rules weren't ever needed and mistakenly added proactively).

[zyga]

@jdstrand the unit tests are failing after those changes

[zyga]

+1

[jdstrand]

Please note that I plan to add a spread test for tun/tap devices in particular, but due to time constraints it needs to be in a followup PR. Also due to said time constraints, I've only tested that this fixes the udev_enumerate_scan failure. This PR on its own should be safe for 2.28 because it is no worse than what exists now (indeed, it is a lot better-- anything with network-control connected will at least now start).

[codecov-io]

Codecov Report

Merging #4031 into master will not change coverage.
The diff coverage is n/a.

@@           Coverage Diff           @@
##           master    #4031   +/-   ##
=======================================
  Coverage   75.88%   75.88%           
=======================================
  Files         431      431           
  Lines       36915    36915           
=======================================
  Hits        28014    28014           
  Misses       6948     6948           
  Partials     1953     1953

Impacted Files	Coverage Δ
interfaces/builtin/network_control.go	100% <ø> (ø)	⬆️

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