[microsite] Add edit button to docs (#2126)

docs/overview/what-is-backstage.md

@@ -18,12 +18,15 @@ Out of the box, Backstage includes:
 - [Backstage Service Catalog](../features/software-catalog/index.md) for
   managing all your software (microservices, libraries, data pipelines,
   websites, ML models, etc.)
+
 - [Backstage Software Templates](../features/software-templates/index.md) for
   quickly spinning up new projects and standardizing your tooling with your
   organization’s best practices
+
 - [Backstage TechDocs](../features/techdocs/README.md) for making it easy to
   create, maintain, find, and use technical documentation, using a "docs like
   code" approach
+
 - Plus, a growing ecosystem of
   [open source plugins](https://github.com/spotify/backstage/tree/master/plugins)
   that further expand Backstage’s customizability and functionality
@@ -33,12 +36,15 @@ Out of the box, Backstage includes:
 - For _engineering managers_, it allows you to maintain standards and best
   practices across the organization, and can help you manage your whole tech
   ecosystem, from migrations to test certification.
+
 - For _end users_ (developers), it makes it fast and simple to build software
   components in a standardized way, and it provides a central place to manage
   all projects and documentation.
+
 - For _platform engineers_, it enables extensibility and scalability by letting
   you easily integrate new tools and services (via plugins), as well as
   extending the functionality of existing ones.
+
 - For _everyone_, it’s a single, consistent experience that ties all your
   infrastructure tooling, resources, standards, owners, contributors, and
   administrators together in one place.