Add workflow to handle regressions

[justinretzolk]

Community Note

• Please vote on this pull request by adding a 👍 reaction to the original pull request comment to help the community and maintainers prioritize this request
• Please do not leave "+1" or other comments that do not add relevant new information or questions, they generate extra noise for pull request followers and do not help prioritize the request
• The resources and data sources in this provider are generated from the CloudFormation schema, so they can only support the actions that the underlying schema supports. For this reason submitted bugs should be limited to defects in the generation and runtime code of the provider. Customizing behavior of the resource, or noting a gap in behavior are not valid bugs and should be submitted as enhancements to AWS via the CloudFormation Open Coverage Roadmap.

About

Adds a workflow to handle regressions:

• Adds prioritized label
• Ensures the item is on the top of the working board

We need to ensure the following secrets exist in the repo:

Slack related:

• SLACK_BOT_TOKEN
• SLACK_CHANNEL

Relates #1742
Depends on #1743

[jar-b]

LGTM

[breathingdust]

LGTM 🚀