Cilium: add 1.16+ metrics

[antonipp]

What does this PR do?

This adds two new metrics released in Cilium 1.16: https://docs.cilium.io/en/v1.16/operations/upgrade/#added-metrics

• cilium_fqdn_selectors
• cilium_identity_label_sources

Motivation

Keep integration up-to-date

Review checklist (to be filled by reviewers)

• Feature or bugfix MUST have appropriate tests (unit, integration, e2e)
• Add the qa/skip-qa label if the PR doesn't need to be tested during QA.
• If you need to backport this PR to another branch, you can add the backport/<branch-name> label to the PR and it will automatically open a backport PR once this one is merged

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 88.04%. Comparing base (d6358fb) to head (ade1f67).
Report is 30 commits behind head on master.

Additional details and impacted files

Flag	Coverage Δ
activemq	?
cassandra	?
cilium	77.92% <ø> (?)
hive	?
hivemq	?
hudi	?
ignite	?
jboss_wildfly	?
kafka	?
presto	?
solr	?

Flags with carried forward coverage won't be shown. Click here to find out more.

[dkirov-dd]

lgtm 👍