[CNVM]: CloudFormation template to support AWS accounts without default VPC

### Integration Name

Security Posture Management [cloud_security_posture]

### Dataset Name

_No response_

### Integration Version

1.12.0

### Agent Version

8.17.3

### OS Version and Architecture

AWS

### User Goal

The CloudFormation template to roll out CNVM Integration, expects a default VPC to exist in the region where it's intended to be rolled out.
Why should a user be forced to use a default VPC, there might be other better suited VPCs around.

Additionally to that, when creating the resource in a private network, the result printing of the public IP makes the whole Cloud Formation Stack to be rolled back, because in a private network, no public IP.

### Existing Features

forces users to use default VPC.

### What did you see?

The rollout breaks when there is no default VPC in a region where to roll out the CNVM VM.

### Anything else?

see attached updated CF template, which has the following additions:

- two new parameters: DefaultVPC, DefaultSubnet
- allows to the user to choose VPC and subnet to place the VM inside
- removed output of the Public IP:
- since there's no reason to have a public IP assigned to that VM, a user might want to place it in a private subnet, where no public IP will be assigned to the VM.
- alternatively, could add internal IP to the Outputs

[cnvm_cf_template.txt](https://github.com/user-attachments/files/19702801/cnvm_cf_template.txt)