1. Add supervisord as the entrypoint of docker-macsec
2. Add wpa_supplicant conf into docker-macsec
3. Set the macsecmgrd as the critical_process
4. Configure supervisor to monitor macsecmgrd
5. Set macsec in the features list
6. Add config variable `INCLUDE_MACSEC`
7. Add macsec.service

**- How to verify it**

Change the `/etc/sonic/config_db.json` as follow
```
{
    "PORT": {
        "Ethernet0": {
            ...
            "macsec": "test"
         }
    }
    ...
    "MACSEC_PROFILE": {
        "test": {
            "priority": 64,
            "cipher_suite": "GCM-AES-128",
            "primary_cak": "0123456789ABCDEF0123456789ABCDEF",
            "primary_ckn": "6162636465666768696A6B6C6D6E6F707172737475767778797A303132333435",
            "policy": "security"
        }
    }
}
```
To execute `sudo config reload -y`, We should find the following new items were inserted in app_db of redis
```
127.0.0.1:6379> keys *MAC*
1) "MACSEC_EGRESS_SC_TABLE:Ethernet0:72152375678227538"
2) "MACSEC_PORT_TABLE:Ethernet0"
127.0.0.1:6379> hgetall "MACSEC_EGRESS_SC_TABLE:Ethernet0:72152375678227538"
1) "ssci"
2) ""
3) "encoding_an"
4) "0"
127.0.0.1:6379> hgetall "MACSEC_PORT_TABLE:Ethernet0"
 1) "enable"
 2) "false"
 3) "cipher_suite"
 4) "GCM-AES-128"
 5) "enable_protect"
 6) "true"
 7) "enable_encrypt"
 8) "true"
 9) "enable_replay_protect"
10) "false"
11) "replay_window"
12) "0"
```

Signed-off-by: Ze Gan <ganze718@gmail.com>