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
assertMsg(logger, checkedFields.map(), checkedArrayFields.map());
        
        CapturingLogger.output(logger.getName(), Level.INFO).clear();
        updateLoggerSettings(
            Settings.builder().put(settings).put("xpack.security.audit.logfile.events.exclude", "tampered_request").build()
        );
        auditTrail.tamperedRequest(requestId, "_action", request);
        assertEmptyLog(logger);
    }
    public void testTamperedRequestWithUser() throws Exception {
        final TransportRequest request = randomBoolean() ? new MockRequest(threadContext) : new MockIndicesRequest(threadContext);
        final String requestId = randomRequestId();
        MapBuilder<String, String> checkedFields = new MapBuilder<>(commonFields);
        MapBuilder<String, String[]> checkedArrayFields = new MapBuilder<>();
        Authentication authentication = createAuthentication();
        auditTrail.tamperedRequest(requestId, authentication, "_action", request);
        checkedFields.put(LoggingAuditTrail.EVENT_TYPE_FIELD_NAME, LoggingAuditTrail.TRANSPORT_ORIGIN_FIELD_VALUE)
            .put(LoggingAuditTrail.EVENT_ACTION_FIELD_NAME, "tampered_request")
            .put(LoggingAuditTrail.ACTION_FIELD_NAME, "_action")
            .put(LoggingAuditTrail.REQUEST_NAME_FIELD_NAME, request.getClass().getSimpleName())
            .put(LoggingAuditTrail.REQUEST_ID_FIELD_NAME, requestId);
        authentication(authentication, checkedFields);
        restOrTransportOrigin(request, threadContext, checkedFields);
        indicesRequest(request, checkedFields, checkedArrayFields);
        opaqueId(threadContext, checkedFields);
        traceId(threadContext, checkedFields);
        forwardedFor(threadContext, checkedFields);
        assertMsg(logger, checkedFields.map(), checkedArrayFields.map());
        CapturingLogger.output(logger.getName(), Level.INFO).clear();