(aws_events_targets): Add Glue WorkFlow as an EventBridge target

### Description

Glue WorkFlow is not currently available as an EventBridge Target, but was added as a valid target last year (2021).

Until this is implemented, I'm having to use a custom Lambda to trigger the workflow, which is much more convoluted.
... or use the level 1 events.CfnRule construct, with events.CfnRule.TargetProperty as a target.

### Use Case

To be able to trigger a GlueWorkflow from EventBridge

### Proposed Solution

na

### Other information

_No response_

### Acknowledge

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

Start by locating the aws_events_targets EventBridge target implementations and reviewing how existing targets are represented and tested. Compare those entry points with the AWS Glue Workflow target requirements, then add coverage showing that an EventBridge rule can target a Glue Workflow; done when the target is available without a custom Lambda or level 1 construct.

Written by the indexing model from the issue text.