fix: Disable port 8081 (metrics) for NiFi 2.x

[Maleware]

This PR adds:

• disable metrics 8081 port if nifi is not 1.x.x

[maltesander]

I dont see the point in adding nifi.web.https.network.interface.lo per default. This can be documented as override for local development?

Edit:
Tests do not work, cannot access UI via Nodeport etc.

HTTPSConnectionPool(host='nifi-node-default-1.nifi-node-default.kuttl-test-measured-sloth.svc.cluster.local', port=8443): Max retries exceeded with url: /nifi-api/access/token (Caused by NewConnectionError('<urllib3.connection.HTTPSConnection object at 0x71c838a1aab0>: Failed to establish a new connection: [Errno 111] Connection refused'))
    logger.go:42: 12:21:22 | smoke_nifi-1.28.1_zookeeper-3.9.3_openshift-false_listener-class-external-unstable/60-prepare-test-nifi | command terminated with exit code 1
    logger.go:42: 12:21:22 | smoke_nifi-1.28.1_zookeeper-3.9.3_openshift-false_listener-class-external-unstable/60-prepare-test-nifi | command failure, skipping 1 additional commands
    logger.go:42: 12:21:23 | smoke_nifi-1.28.1_zookeeper-3.9.3_openshift-false_listener-class-external-unstable/60-prepare-test-nifi | test step failed 60-prepare-test-nifi
    case.go:396: failed in step 60-prepare-test-nifi
    case.go:398: command "kubectl exec -n $NAMESPACE test-nifi-0 -- python /tmp/test_nifi.py ..." failed, exit status 1
    logger.go:42: 12:21:23 | smoke_nifi-1.28.1_zookeeper-3.9.3_openshift-false_listener-class-external-unstable | skipping kubernetes event logging
=== NAME  kuttl
    harness.go:403: run tests finished
    harness.go:510: cleaning up
    harness.go:567: removing temp folder: ""
--- FAIL: kuttl (463.10s)
    --- FAIL: kuttl/harness (0.00s)
        --- FAIL: kuttl/harness/smoke_nifi-1.28.1_zookeeper-3.9.3_openshift-false_listener-class-external-unstable (463.09s)

Even though the docs state this should be additive, i dont feel this works properly....

[maltesander]

Changelog is missing.

[maltesander]

LGTM!

[lfrancke]

Can you please add some justification to this issue? Why do we disable the port? Does this need to be mentioned in the release notes? Does this need to be documented?

[maltesander]

It is only disabled for version 2.x.x since the metrics endpoint changed. Nothing breaking, was never used in 2.x.x, reporting task job is deactivated for 2.x.x as well. We just still exposed the "non-existent" metrics port in 2.x.x so far, which is fixed by this.

[lfrancke]

Thank you