feat: alternative vpc configuration for workflows api

[botanical]

Summary: Summary of changes

Addresses VEDA-146: Develop amazing new feature

Changes

• Updated main.tf to create a security group for the workflows API lambda
• Updated main.tf to set up VPC for the workflows API lambda
• Updated the necessary variables, etc, files and tested with a local deployment

PR Checklist

• Update CHANGELOG
• Unit tests
• Ad-hoc testing - Deploy changes and test manually
• Integration tests

[botanical]

I suppose this is technically accurate but maybe we should add guidance on what subnet IDs should be set since the VPC ID is inferred from those values. 🤔