Some types of audit event samples from [our documentation](https://www.elastic.co/guide/en/elasticsearch/reference/7.17/audit-event-types.html) include the port number in "origin.address", like **access_denied**:
```json
{"type":"audit", "timestamp":"2020-12-30T22:30:06,949+0200", "node.id":
"0RMNyghkQYCc_gVd1G6tZQ", "event.type":"transport", "event.action":
"access_denied", "authentication.type":"REALM", "user.name":"user1",
"user.realm":"default_native", "user.roles":["test_role"], "origin.type":
"rest", "origin.address":"[::1]:52434", "request.id":"yKOgWn2CRQCKYgZRz3phJw",
"action":"indices:admin/auto_create", "request.name":"CreateIndexRequest",
"indices":["<index-{now/d+1d}>"]}
```
but other types like **connection_denied** from this issue does not include the port:

```json
{"type":"audit", "timestamp":"2020-12-30T21:47:31,526+0200", "node.id":
"0RMNyghkQYCc_gVd1G6tZQ", "event.type":"ip_filter", "event.action":
"connection_denied", "origin.type":"rest", "origin.address":"10.10.0.20",
"transport.profile":".http", "rule":"deny 10.10.0.0/16"}
```

I think we should be consistent here and always include the port number in the "origin.address" field.
x-pack/plugin/security/src/test/java/org/elasticsearch/xpack/security/audit/logfile/LoggingAuditTrailFilterTests.java
private static final String FILTER_MARKER = "filterMarker_";
    private static final String UNFILTER_MARKER = "nofilter_";
    private Settings settings;
    private DiscoveryNode localNode;
    private ClusterService clusterService;
    private ApiKeyService apiKeyService;
    @Before
    public void init() throws Exception {
        settings = Settings.builder()
            .put(LoggingAuditTrail.EMIT_HOST_ADDRESS_SETTING.getKey(), randomBoolean())
            .put(LoggingAuditTrail.EMIT_HOST_NAME_SETTING.getKey(), randomBoolean())
            .put(LoggingAuditTrail.EMIT_NODE_NAME_SETTING.getKey(), randomBoolean())
            .put(LoggingAuditTrail.EMIT_NODE_ID_SETTING.getKey(), randomBoolean())
            .put(LoggingAuditTrail.EMIT_CLUSTER_NAME_SETTING.getKey(), randomBoolean())
            .put(LoggingAuditTrail.EMIT_CLUSTER_UUID_SETTING.getKey(), randomBoolean())
            .put(ClusterName.CLUSTER_NAME_SETTING.getKey(), randomAlphaOfLength(16))
            .put(LoggingAuditTrail.INCLUDE_REQUEST_BODY.getKey(), randomBoolean())
            .put(LoggingAuditTrail.INCLUDE_EVENT_SETTINGS.getKey(), "_all")
            .build();
        localNode = mock(DiscoveryNode.class);
        when(localNode.getHostAddress()).thenReturn(buildNewFakeTransportAddress().toString());
        final ClusterState clusterState = ClusterState.builder(ClusterName.CLUSTER_NAME_SETTING.get(settings))
            .metadata(Metadata.builder().clusterUUID(UUIDs.randomBase64UUID()).build())
            .build();
        clusterService = mock(ClusterService.class);
        when(clusterService.localNode()).thenReturn(localNode);
        when(clusterService.getClusterName()).thenReturn(ClusterName.CLUSTER_NAME_SETTING.get(settings));