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
Optional.of(randomFrom(filteredUsers)),
                        Optional.of(randomFrom(filteredRealms)),
                        Optional.of(authzInfo(someRolesDoNotMatch.toArray(new String[0]))),
                        Optional.of(randomSubsetOf(randomIntBetween(1, filteredIndices.size()), filteredIndices).toArray(new String[0])),
                        Optional.of(randomFrom(filteredActions))
                    )
                )
        );
        final Optional<AuthorizationInfo> emptyRoles = randomBoolean() ? Optional.empty() : Optional.of(authzInfo(new String[0]));
        assertTrue(
            "Matches the filter predicate because of the empty roles.",
            auditTrail.eventFilterPolicyRegistry.ignorePredicate()
                .test(
                    new AuditEventMetaInfo(
                        Optional.of(randomFrom(filteredUsers)),
                        Optional.of(randomFrom(filteredRealms)),
                        emptyRoles,
                        Optional.of(randomSubsetOf(randomIntBetween(1, filteredIndices.size()), filteredIndices).toArray(new String[0])),
                        Optional.of(randomFrom(filteredActions))
                    )
                )
        );
        final List<String> someIndicesDoNotMatch = new ArrayList<>(
            randomSubsetOf(randomIntBetween(0, filteredIndices.size()), filteredIndices)
        );
        for (int i = 0; i < randomIntBetween(1, 8); i++) {
            someIndicesDoNotMatch.add(UNFILTER_MARKER + randomAlphaOfLengthBetween(1, 8));
        }
        assertFalse(
            "Does not match the filter predicate because of some of the indices.",