Add an option to fail on a skipped check

### Details

We have a scenario where we want to skip a certain check for the development environment but not for stage and production. With the current setup (as I understand it from looking at the code here [link](https://github.com/github/branch-deploy/blob/d1f158e5cd122a1db00e8ba49044134fd641ae21/dist/index.js#L44046C9-L44046C29)) skipped check is considered healthy. It would be convient for us to have an option like skipped_checks: true/false (fail if it is set to false as we would like it to be here)

Start with the skipped-check handling in dist/index.js at the linked location, then trace how check results and configuration options are parsed and evaluated. Confirm how an option such as skipped_checks would affect deployment checks, and verify that skipped checks can be treated as failures where configured without changing the existing default behavior.

Written by the indexing model from the issue text.