replace AWS ec2 module with aws_instance resource definitions

[mgogoulos]

📋 User requirements

What

In the provisioning of ec2 instances, it's more flexible to move from the ec2 module to aws_instance. This will allow better control of custom parameters and also addition of new nodes with different specs.

Make each cluster node have separate aws_instance resource definitions.

✅ Acceptance criteria

No response

🛸 Out of scope

No response

📝 Additional context (Optional)

No response

🕸️ Dependencies (Optional)

No response

🖼️ Wireframe (Optional)

No response