Remove Overview header from pages

doc/ci/metrics_reports.md

@@ -9,8 +9,6 @@ type: reference
 
 > [Introduced](https://gitlab.com/gitlab-org/gitlab/-/issues/9788) in [GitLab Premium](https://about.gitlab.com/pricing/) 11.10. Requires GitLab Runner 11.10 and above.
 
-## Overview
-
 GitLab provides a lot of great reporting tools for [merge requests](../user/project/merge_requests/index.md) - [Unit test reports](unit_test_reports.md), [code quality](../user/project/merge_requests/code_quality.md), performance tests, etc. While JUnit is a great open framework for tests that "pass" or "fail", it is also important to see other types of metrics from a given change.
 
 You can configure your job to use custom Metrics Reports, and GitLab will display a report on the merge request so that it's easier and faster to identify changes without having to check the entire log.

doc/ci/unit_test_reports.md

@@ -10,8 +10,6 @@ type: reference
 > - [Introduced](https://gitlab.com/gitlab-org/gitlab-foss/-/issues/45318) in GitLab 11.2. Requires GitLab Runner 11.2 and above.
 > - [Renamed](https://gitlab.com/gitlab-org/gitlab/-/merge_requests/39737) from JUnit test reports to Unit test reports in GitLab 13.4.
 
-## Overview
-
 It is very common that a [CI/CD pipeline](pipelines/index.md) contains a
 test job that will verify your code.
 If the tests fail, the pipeline fails and users get notified. The person that