Remove Overview header from pages

doc/user/admin_area/settings/instance_template_repository.md

@@ -9,8 +9,6 @@ type: reference
 
 > [Introduced](https://gitlab.com/gitlab-org/gitlab/-/issues/5986) in [GitLab Premium](https://about.gitlab.com/pricing/) 11.3.
 
-## Overview
-
 In hosted systems, enterprises often have a need to share their own templates
 across teams. This feature allows an administrator to pick a project to be the
 instance-wide collection of file templates. These templates are then exposed to

doc/user/project/issues/design_management.md

@@ -10,8 +10,6 @@ info: "To determine the technical writer assigned to the Stage/Group associated
 > - Support for SVGs was [introduced](https://gitlab.com/gitlab-org/gitlab/-/issues/12771) in [GitLab Premium](https://about.gitlab.com/pricing/) 12.4.
 > - Design Management was [moved](https://gitlab.com/gitlab-org/gitlab/-/issues/212566) to GitLab Core in 13.0.
 
-## Overview
-
 Design Management allows you to upload design assets (wireframes, mockups, etc.)
 to GitLab issues and keep them stored in one single place, accessed by the Design
 Management's page within an issue, giving product designers, product managers, and engineers a