### Issue # (if applicable)

Closes aws#34861.

### Reason for this change

Creates CDK constructs for CloudWatch Logs Transformers. Transformers already have CFN constructs and this achieves functional parity.

### Description of changes

Added a `Transformer` construct which is an abstraction over `cfnTransformer`.

Created a factory class `ProcessorFactory` with static methods to create each of the 5 overarching types of processors described in https://docs.aws.amazon.com/AmazonCloudWatch/latest/logs/CloudWatch-Logs-Transformation-Processors.html, namely: `ParserProcessor`, `VendedLogParser`, `StringMutatorProcessor`, `JsonMutatorProcessor` and `DataConverterProcessor`. 
These classes implement a `_bind()` method responsible for returning the props expected by CFN constructs for each processor of the respective types.
These classes are further split into their processors defined by enums (`ParserProcessorType`, `VendedLogType`, `StringMutatorType`, `JsonMutatorType`, `DataConverterType`) and properties for each processor.

A `Transformer` expects a `transformerConfig` which is a list of processors. Processors can be created using the static methods `createParserProcessor`, `createVendedLogParser`, `createStringMutatorProcessor`, `createJsonMutatorProcessor` and `createDataConverterProcessor` in the `ProcessorFactory`, by passing the type (from the enums defined above) and the relevant props for that processor. `ValidationError` is thrown if the expected/required props are not passed.

Further validations are performed for limit breaches or positions of parsers being incorrect.

### Describe any new or updated permissions being added

-


### Description of how you validated changes

Added unit tests for each processor and each validation. Added integ 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)

----

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