halt-on-fail option not respected during PHPCS

Problem/Motivation

When a test run includes halt-on-fail: true in the build's assessment steps and there are violations it should:
- Mark the build as a failure
- Set the issue to Needs Work

This is currently not working as expected. For example in #3134162: Fix coding standards violations → , the project was configured with:

phpcs:
  halt-on-fail: true

This causes PHPCS to exit with a status code of 2 but the build is still marked as "successful" and the build label is gray instead of red.

Proposed resolution

Fix Drupal CI so build assessment failures with halt-on-fail: true cause the job to fail.

Remaining tasks

TBD

User interface changes

Build assessment failures with halt-on-fail: true are treated the same as test failures.

API changes

None

Data model changes

None

Release notes snippet

TBD