No rds.force_ssl for AWS RDS MySql

There is no such parameter in Parameter Group for `msql8.0` in `AWS RDS`. See screenshot:

![image](https://user-images.githubusercontent.com/20682846/97026883-9e88f780-1577-11eb-95e5-1b04d5439d15.png)


Please update the docs [here](https://github.com/miztiik/AWS-Demos/tree/master/How-To/setup-ssl-connection-to-rds#forcing-connections-to-your-db-instance-to-use-ssl).