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
when(clusterService.lifecycleState()).thenReturn(Lifecycle.State.STARTED);
        when(clusterService.state()).thenReturn(clusterState);
        final ClusterSettings clusterSettings = mockClusterSettings();
        when(clusterService.getClusterSettings()).thenReturn(clusterSettings);
        Mockito.doAnswer((Answer) invocation -> {
            final LoggingAuditTrail arg0 = (LoggingAuditTrail) invocation.getArguments()[0];
            arg0.updateLocalNodeInfo(localNode);
            return null;
        }).when(clusterService).addListener(Mockito.isA(LoggingAuditTrail.class));
        apiKeyService = new ApiKeyService(
            settings,
            Clock.systemUTC(),
            mock(Client.class),
            mock(SecurityIndexManager.class),
            clusterService,
            mock(CacheInvalidatorRegistry.class),
            mock(ThreadPool.class)
        );
    }
    public void testPolicyDoesNotMatchNullValuesInEvent() throws Exception {
        final Logger logger = CapturingLogger.newCapturingLogger(Level.INFO, null);
        final ThreadContext threadContext = new ThreadContext(Settings.EMPTY);
        final Settings.Builder settingsBuilder = Settings.builder().put(settings);
        
        final List<String> filteredUsernames = randomNonEmptyListOfFilteredNames();
        final List<User> filteredUsers = filteredUsernames.stream().map(u -> { return new User(u); }).collect(Collectors.toList());
        settingsBuilder.putList("xpack.security.audit.logfile.events.ignore_filters.userPolicy.users", filteredUsernames);
        
        final List<String> filteredRealms = randomNonEmptyListOfFilteredNames();
        settingsBuilder.putList("xpack.security.audit.logfile.events.ignore_filters.realmsPolicy.realms", filteredRealms);