ARN decoding functionality

### What problem are you facing?

Being able to decode the ARN fields on AWS objects to get components is handy for populating in IAM Role/Policy templates and other use cases.

I appreciate this is an AWS specific function so would need to be named accordingly e.g. awsArn

Prior art can be found via [terraform](https://registry.terraform.io/providers/hashicorp/aws/latest/docs/data-sources/arn)

### How could this Function help solve your problem?

The use case I'd like to utilise it for is referencing an EKS MR and knowing the region it's deployed in to - as far as I can see the only time this is referenced is the `.status.atProvider.arn` field.

You can play around with sprig's split functionality to split on colons, but that's what utility functions are for right?