ecs-patterns: QueueProcessingEc2Service to expose assignPublicIp

### Describe the feature

Would be nice if QueueProcessingEc2Service will expose assignPublicIp.

### Use Case

When there is a huge outgoing traffic it is cheaper to have Public IP instead of paying for NAT

### Proposed Solution

`assignPublicIp: true`

### Other Information

_No response_

### Acknowledgements

- [ ] I may be able to implement this feature request
- [ ] This feature might incur a breaking change

### CDK version used

2.124.0

### Environment details (OS name and version, etc.)

MacOS

Start with the QueueProcessingEc2Service entry point in ecs-patterns and trace how its service properties are defined and passed through. Check the relevant ecs-patterns tests while determining where assignPublicIp must be exposed; done means the option is accepted and its public-IP behavior is covered by tests.

Written by the indexing model from the issue text.