CI will rebuild after you revert everything and still fail to deploy if you pushed a versioned library from your broken code.
Go into your environment and manually roll back to a working image... and learn a powerful lesson.
Even then it's manageable if your production deployments are version pinned, it only becomes a problem if schemas in your database or messaging have had non compatible changes and data has been written (i.e you have binary and data dependencies in a release)
All this being said with the assumption that the CI/CD pipeline has been designed to best practices.