This reverts commit 764c8203b8.
While this is desireable in principle, some of our modules and services
fail during service startup if no network is available don't currently
properly set Wants=network-online.target.
If nothing pulls in this target anymore, systemd won't try to reach it.
We have many VM tests waiting for `network-online.target`, and after
764c8203b8 fail with the following error
message:
```
error: unit "network-online.target" is inactive and there are no pending jobs
```
Most likely, test scripts shouldn't wait for `network-online.target` in
first place (as `network-online.target` says nothing about whether a
service has been started), but instead, the script should wait for the
network ports of the corresponding service to be open.
Let's revert this for now, and re-apply in a draft PR, fixing the tests
before merging it back in.
15d761a525