wrong compose syntax

https://github.com/docker/labs/blob/1bcbb14346cacd47446934926315e3f4d5222a55/security/apparmor/README.md?plain=1#L266

there should be the next code
```dockerfile
services:
``` 
on top of the `docker-compose.yml` file otherwise you'll receive the error
```shell
 Additional property mysql is not allowed
``` 

Regards