Refactor test reports

What does this MR do?

This MR refactors the rest of the test reports to use the same architecture as the Code Quality one uses after the refactor in https://gitlab.com/gitlab-org/gitlab-ee/merge_requests/7465

• sast
• dast
• container_scanning
• dependency_management

Out of scope:

• license_management
• performance

What are the relevant issue numbers?

Related https://gitlab.com/gitlab-org/gitlab-ee/issues/7125

Does this MR meet the acceptance criteria?

• Changelog entry added, if necessary
• Documentation created/updated
• Tests added for this feature/bug
• Conforms to the code review guidelines
• Conforms to the merge request performance guidelines
• Conforms to the style guides
• N/A Conforms to the database guides
• EE specific content should be in the top level /ee folder
• N/A For a paid feature, have we considered GitLab.com plans, how it works for groups, and is there a design for promoting it to users who aren't on the correct plan?