Re-write end-to-end quick start guide

Make wording and tutorial more terse
Rename quick_start_guide to beginners_guide
Update beginners_guide title
Update quick_start_guide ref links
Apply suggestions to beginners_guide.md
Implement review items
Reduce filesize of image
Fix broken anchor

doc/development/testing_guide/end_to_end/index.md

@@ -180,7 +180,7 @@ instance-level scenarios](https://gitlab.com/gitlab-org/gitlab-foss/tree/master/
 
 Continued reading:
 
-- [Quick Start Guide](quick_start_guide.md)
+- [Beginner's Guide](beginners_guide.md)
 - [Style Guide](style_guide.md)
 - [Best Practices](best_practices.md)
 - [Testing with feature flags](feature_flags.md)

qa/README.md

@@ -46,7 +46,7 @@ the browser to use. You will need to have Chrome (or Chromium) and
 
 ### Writing tests
 
-- [Writing tests from scratch tutorial](../doc/development/testing_guide/end_to_end/quick_start_guide.md)
+- [Writing tests from scratch tutorial](../doc/development/testing_guide/end_to_end/beginners_guide.md)
     - [Best practices](../doc/development/testing_guide/best_practices.md)
     - [Using page objects](../doc/development/testing_guide/end_to_end/page_objects.md)
     - [Guidelines](../doc/development/testing_guide/index.md)