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/LoggingAuditTrailTests.java
threadContext.putHeader(Task.X_OPAQUE_ID_HTTP_HEADER, randomAlphaOfLengthBetween(1, 4));
        }
        if (randomBoolean()) {
            threadContext.putHeader(Task.TRACE_ID, randomAlphaOfLength(32));
        }
        if (randomBoolean()) {
            threadContext.putHeader(
                AuditTrail.X_FORWARDED_FOR_HEADER,
                randomFrom("2001:db8:85a3:8d3:1319:8a2e:370:7348", "203.0.113.195", "203.0.113.195, 70.41.3.18, 150.172.238.178")
            );
        }
        logger = CapturingLogger.newCapturingLogger(randomFrom(Level.OFF, Level.FATAL, Level.ERROR, Level.WARN, Level.INFO), patternLayout);
        auditTrail = new LoggingAuditTrail(settings, clusterService, logger, threadContext);
        apiKeyService = new ApiKeyService(
            settings,
            Clock.systemUTC(),
            client,
            securityIndexManager,
            clusterService,
            mock(CacheInvalidatorRegistry.class),
            mock(ThreadPool.class)
        );
    }
    @After
    public void clearLog() throws Exception {
        CapturingLogger.output(logger.getName(), Level.INFO).clear();
    }
    public void testEventsSettingValidation() {
        final String prefix = "xpack.security.audit.logfile.events.";
        Settings settings = Settings.builder().putList(prefix + "include", Arrays.asList("access_granted", "bogus")).build();