TEAM #1177 - Adds delete step to task definition cleanup workflow

[coreycarvalho]

Description

#2204 implemented a GHA workflow to deregister task definitions, keeping up to the most recent 10 revisions. This PR adds a step to that workflow to delete ALL inactive task definitions in batches of 10 (maximum allowed by AWS API). The workflow step also adds jitter and exponential backoff to prevent being rate limited by the AWS API.

issue TEAM 1177

How Has This Been Tested?

https://github.com/department-of-veterans-affairs/notification-api/actions/runs/12517536138/job/34918494673#step:5:1 -- this contains the dry run of the workflow.

Checklist

• I have assigned myself to this PR
• PR has an appropriate title: #9999 - What the thing does
• PR has a detailed description, including links to specific documentation
• I have added the appropriate labels to the PR.
• I did not remove any parts of the template, such as checkboxes even if they are not used
• My code follows the style guidelines of this project
• I have performed a self-review of my own code
• I have commented my code, particularly in hard-to-understand areas
• I have made corresponding changes to any documentation
• My changes generate no new warnings
• I have added tests that prove my fix is effective or that my feature works. Testing guidelines
• I have ensured the latest main is merged into my branch and all checks are green prior to review
• New and existing unit tests pass locally with my changes
• Any dependent changes have been merged and published in downstream modules
• The ticket was moved into the DEV test column when I began testing this change