Fix cobertura to coverage_report

Given recent security fixes on GitLab, the keyword for coverage reports have evolved from the single key cobertura.

This MR addresses this issue.

Details about the problem can be found here:

• https://about.gitlab.com/releases/2022/07/28/security-release-gitlab-15-2-1-released/
• https://gitlab.com/gitlab-org/gitlab/-/issues/344533