Remove negative lookahead from CI config
This has been deprecated since 11.9.4. Switching to the syntax recommended in https://about.gitlab.com/2019/04/01/security-release-gitlab-11-dot-9-dot-4-released/#example-2
This has been deprecated since 11.9.4. Switching to the syntax recommended in https://about.gitlab.com/2019/04/01/security-release-gitlab-11-dot-9-dot-4-released/#example-2