feat(sns): add notExistsCondition method (#34712)

### Issue # (if applicable)

Closes #34707 

### Reason for this change

Set subscription filter with exists `false` for a property.

### Description of changes

Add new `notExistsCondition()` method.

### Describe any new or updated permissions being added

None.


### Description of how you validated changes

Extended existing integration test.

### Checklist
- [X] My code adheres to the [CONTRIBUTING GUIDE](https://github.com/aws/aws-cdk/blob/main/CONTRIBUTING.md) and [DESIGN GUIDELINES](https://github.com/aws/aws-cdk/blob/main/docs/DESIGN_GUIDELINES.md)

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*By submitting this pull request, I confirm that my contribution is made under the terms of the Apache-2.0 license*

Author: jaw111