Network Manager sets USB Ethernet to unmanaged in fresh Lunar

[Michał J. Gajda]

After installing a recent build of Lunar, the wired connection stopped working.

It appears that default configuration in
`/usr/lib/NetworkManager/conf.d/10-globally-managed-devices.conf` sets all wired ethernet to _strictly unmanaged_, whereas USB ethernet should be strictly managed:
```
[keyfile]
unmanaged-devices=*,except:type:wifi,except:type:gsm,except:type:cdma
```

Since unmanaged devices are never brought up, it seems that all `ethernet` devices should be managed anyway.

Detailed description of the problem and solution:
https://jbit.net/NetworkManager_Strictly_Unmanaged/

Related to #279262

ProblemType: Bug
DistroRelease: Ubuntu 23.04
Package: network-manager 1.40.12-1ubuntu1 [modified: usr/lib/NetworkManager/conf.d/10-globally-managed-devices.conf]
ProcVersionSignature: Ubuntu 6.1.0-16.16-generic 6.1.6
Uname: Linux 6.1.0-16-generic x86_64
ApportVersion: 2.26.0-0ubuntu2
Architecture: amd64
CRDA: N/A
CasperMD5CheckResult: pass
CurrentDesktop: ubuntu:GNOME
Date: Wed Mar 8 17:25:29 2023
InstallationDate: Installed on 2023-03-05 (3 days ago)
InstallationMedia: Ubuntu 23.04 "Lunar Lobster" - Alpha amd64 (20230301.1)
ProcEnviron:
 LANG=en_US.UTF-8
 PATH=(custom, no user)
 SHELL=/bin/bash
 TERM=xterm-256color
 XDG_RUNTIME_DIR=<set>
SourcePackage: network-manager
UpgradeStatus: No upgrade log present (probably fresh install)
nmcli-nm:
 RUNNING VERSION STATE STARTUP CONNECTIVITY NETWORKING WIFI-HW WIFI WWAN-HW WWAN
 running 1.40.12 connected started full enabled enabled disabled missing enabled