Because we no longer have a top nav

Related to
https://gitlab.com/gitlab-org/technical-writing/-/issues/773#note_1326235371

Because the repo has changed

Needed to assign failure issues

Related epic: https://gitlab.com/groups/gitlab-com/-/epics/1940

Update tree, blob, issue links to gitlab-org/gitlab with a new format
that includes /-/ scope.

Signed-off-by: Dmitriy Zaporozhets <dmitriy.zaporozhets@gmail.com>

Related to: https://gitlab.com/gitlab-org/gitlab/-/issues/291023

Revise internal handbook link due to change.

In https://gitlab.com/groups/gitlab-org/-/epics/5020, we decided to
use only two alerts (note, warning), and eliminate any bold text
coming after the icon.

This changes CAUTION to WARNING and eliminates any
**Warning:**/**Caution:** text that comes after them.

The previous URL had two drawbacks:

1. It didn't match what the title was about (`Assignments to DevOps
   Stages and Groups`, and the anchor was `#designated-technical-writers`).
2. It didn't account for the other sections, like development and API
   guidelines.

These pages used future tense, instead of the present tense, which
is GitLab tone and style. No substantive changes to content were made.

Re-flow notes into body text, on pages not owned by a specific stage.

Yet more pages that need to be marked as "none" for stages.

https://relishapp.com/rspec/rspec-core/docs/subject/explicit-subject
recommends named subjects also

Signed-off-by: Takuya Noguchi <takninnovationresearch@gmail.com>

Update QA docs to reflect changes from
RSpec 4.0 monkey patching

Many handbook pages were changes, redirected, or
deleted. Updates all affected links

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