Update MAC address vendor lookup link (#1390)

README.md

@@ -271,7 +271,7 @@ API | Description | Auth | HTTPS | CORS |
 | [JSONbin.io](https://jsonbin.io) | Free JSON storage service. Ideal for small scale Web apps, Websites and Mobile apps | `apiKey` | Yes | Yes |
 | [Judge0](https://api.judge0.com/) | Compile and run source code | No | Yes | Unknown |
 | [License-API](https://github.com/cmccandless/license-api/blob/master/README.md) | Unofficial REST API for choosealicense.com | No | Yes | No |
-| [MAC address vendor lookup](https://macaddress.io) | Retrieve vendor details and other information regarding a given MAC address or an OUI | `apiKey` | Yes | Yes |
+| [MAC address vendor lookup](https://macaddress.io/api) | Retrieve vendor details and other information regarding a given MAC address or an OUI | `apiKey` | Yes | Yes |
 | [Nationalize.io](https://nationalize.io) | Estimate the nationality of a first name | No | Yes | Yes |
 | [OOPSpam](https://oopspam.com/) | Multiple spam filtering service | No | Yes | Yes |
 | [Plino](https://plino.herokuapp.com/) | Spam filtering system | No | Yes | Unknown |