[Website]: Include "Add a data tier" and "Disable a Data Tier" in sidebar links

[rseldner]

Type of issue

Other

What documentation page is affected

https://www.elastic.co/docs/manage-data/lifecycle/data-tiers

What happened?

We used to have a dedicated Disable an Elasticsearch data tier page in our EC docs that was very easy to locate

ECH: https://www.elastic.co/guide/en/cloud/current/ec-disable-data-tier.html (this redirects now)
ECE: https://www.elastic.co/guide/en/cloud-enterprise/3.8/ece-disable-data-tier.html

This page has been merged into this general data tiers doc and it's sort of buried in there in between the ECH/ECE and self-managed deployments sections. It is not obvious where in the overall page it is located.
https://www.elastic.co/docs/manage-data/lifecycle/data-tiers

So I wonder if the headings should be tweaked so the Disable a Data Tier section appears in the sidebar.

Additional info

Opinion: The organization of the merged docs has made things more difficult to locate.

[shainaraskas]

this is a limitation of our on this page structure (only has two levels) - we could consider breaking up these pages possibly