AWS::EC2:VPNConnection - Add support for enabling VPN Logs for each individual tunnel.

### Name of the resource

AWS::EC2::VPNConnection

### Resource name

AWS::EC2::VPNConnection

### Description

Hi,

AWS::EC2:VPNConnection currently does not support the option of enabling [VPN logs](https://docs.aws.amazon.com/vpn/latest/s2svpn/monitoring-logs.html).

When this issue is closed we should be able to do the following for each tunnel:

1. Specify what Amazon CloudWatch log group to send logs
2. Select output format json or text

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Closely related to [Issue 429](https://github.com/aws-cloudformation/cloudformation-coverage-roadmap/issues/429).

### Other Details

https://docs.aws.amazon.com/vpn/latest/s2svpn/monitoring-logs.html

Start with the AWS::EC2::VPNConnection resource and read the linked VPN monitoring logs documentation. Review related issue 429 for context and determine how per-tunnel CloudWatch log groups and JSON or text output should be represented. Done means the resource supports both requested logging settings for each tunnel.

Written by the indexing model from the issue text.