Changes to HA docs to inc different architecture types
What does this MR do?
Resolves part of https://gitlab.com/gitlab-org/gitlab-ce/issues/44800.
Points of interest
- We can backport to CE later
- Adds the tier badge for each section (Core, Premium) as appropriate.
- Create two top-level headings, one each for Scaled and HA.
- Mentions relevant architectures with links at the top of each section
- Links back to the relevant sections at the bottom of each section
- Trying to keep to a minimal viable change
- Add scaling sections. Link to each from the 'Basic Scaling' section on the index page.
- Wait to complete other scaling and HA installation instructions for later iteration.
- Avoid major changes to the HA sections except for changes to heading depth. Fully-knowing that these sections need some updates, too. Let's keep that for a later iteration.
- Even with these in mind, the changeset here will be quite large
- Use the review app links to see the changes visually
What are the relevant issue numbers?
Does this MR meet the acceptance criteria?
- Changelog entry added, if necessary
- Documentation created/updated via this MR
- Tests added for this feature/bug
- Tested in all supported browsers
- Conforms to the code review guidelines
- Conforms to the merge request performance guidelines
- Conforms to the style guides
- Conforms to the database guides
- Link to e2e tests MR added if this MR has Requires e2e tests label. See the Test Planning Process.
EE specific content should be in the top level
- For a paid feature, have we considered GitLab.com plans, how it works for groups, and is there a design for promoting it to users who aren't on the correct plan?
- Security reports checked/validated by reviewer