CHAOSPLT-82: Affect localhost interface for pod level network disruptions

[ptnapoleon]

What does this PR do?

• Adds new functionality
• Alters existing functionality
• Fixes a bug
• Improves documentation or testing

Please briefly describe your changes as well as the motivation behind them:

• Pod level network disruptions should target the localhost network interface. Previously we explicitly avoided this interface on all network disruptions, because, as far as im aware, we were worried about affecting kubelet's behaviors on the node. This should be safe for us to do on pod level disruptions, though. There are applications we're currently unable to network disrupt because they send traffic via localhost, and we fail to filter that with our tc rules.
• I've made a change to the netlink.go to add logging, and to take a boolean parameter to decide if we should include the "lo" interface. Whenever we're using a pod level disruption, we set this to true in network_disruption.go
• I didn't add any new unit tests. I tried to add a netlink_test.go, but the call to links, err := netlink.LinkList() within netlink.go would error when run as a unit test, and we don't have mocks for that library

Code Quality Checklist

• The documentation is up to date.
• My code is sufficiently commented and passes continuous integration checks.
• I have signed my commit (see Contributing Docs).

Testing

• I leveraged continuous integration testing
  • by depending on existing unit tests or end-to-end tests.
  • by adding new unit tests or end-to-end tests.
• I manually tested the following steps:
  • x
  • locally.
  • as a canary deployment to a cluster.

[datadog-datadog-prod-us1]

Datadog Report

Branch report: phil/chaos-789
Commit report: 40fcf16

✅ chaos-controller: 0 Failed, 0 New Flaky, 666 Passed, 0 Skipped, 7m 13.54s Wall Time