docs: Add ALB endpoint to examples/fargate output

[setheliot]

Description

Add ALB endpoint to outputs for the fargate example

Motivation and Context

• After running terraform apply, this makes it easier to find the ALB endpoint and test the deployment
• This makes the fargate example consistent with the other two (docs: Add ALB endpoint to example outputs #256)

Breaking Changes

No

How Has This Been Tested?

• I have updated at least one of the examples/* to demonstrate and validate my change(s)
• I have tested and validated these changes using one or more of the provided examples/* projects

• I have executed pre-commit run -a on my pull request