[Inventory] Remove the new services inventory docs

[alaudazzi]

Description

This PR removes the new services inventory documentation as it is superseded by the new Inventory page (#4341) .

Documentation sets edited in this PR

Check all that apply.

• Stateful (docs/en/observability/*)
• Serverless (docs/en/serverless/*)
• Integrations Developer Guide (docs/en/integrations/*)
• None of the above

Related issues

• [Request]: Create new inventory docs and remove docs for new service inventory #4254
• [Inventory] Create new Inventory docs #4341

Checklist

• Product/Engineering Review
• Writer Review

Follow-up tasks

Select one.

• This PR does not need to be ported to another doc set because:
  • The concepts in this PR only apply to one doc set (serverless or stateful)
  • The PR contains edits to both doc sets (serverless and stateful)
• This PR needs to be ported to another doc set:
  • Port to stateful docs: [Inventory] Port #4342 to stateful docs #4347
  • Port to serverless docs: <link to PR or tracking issue>

[mergify]

This pull request does not have a backport label. Could you fix it @alaudazzi? 🙏
To fixup this pull request, you need to add the backport labels for the needed
branches, such as:

• backport-/d./d is the label to automatically backport to the /d./d branch. /d is the digit
  NOTE: backport-skip has been added to this pull request.

[roshan-elastic]

LGTM!

[colleenmcginnis]

It looks like there are links to the page you deleted in two files that need to be updated or removed:

• docs/en/serverless/elastic-entity-model.mdx (2 instances)
• docs/en/serverless/apm/apm-ui-services.mdx (1 instance)

[alaudazzi]

Thank you for your review @colleenmcginnis!
I updated the docs/en/serverless/apm/apm-ui-services.mdx by removing the reference for now. When we have more solid content for Inventory, we can put it back, if needed.

docs/en/serverless/elastic-entity-model.mdx is being updated in #4340, so broken links are expected.

[mdbirnstiehl]

🦭

[elasticdocs]

🚀 Built elastic-dot-co-docs-preview-docs successfully!

• https://elastic-dot-co-docs-production-9r4k8w0bb-elastic-dev.vercel.app

• Built with commit 1823eb6

Issues? Visit #next-docs in Slack