Analyze VPC firewall reports and write rules to restrict traffic

A while ago, a VPC firewall with its first set of rules was implemented in Staging to start restricting incoming and outgoing traffic (https://github.com/cds-snc/forms-terraform/pull/1294). It had been set up in a way that did not put too much restrictions on the flowing traffic.

We now have collected enough data to allow us to write new firewall rules in order to have full control over what comes in and goes out of the VPC.

- [ ] Analyze AWS VPC firewall reports and determine list of domains that should be allowed (https://docs.google.com/spreadsheets/d/1mXd39laqprSoV6oNQztCT-kqfiZKlpzGDZzgkBOA1SQ)
- [ ] Implement new set of firewall rules (https://github.com/cds-snc/forms-terraform/pull/1433)