Backport of docs - remove Sentinel from enterprise features list into release/1.16.x

[hc-github-team-consul-core]

Backport

This PR is auto-generated from #18176 to be assessed for backporting due to the inclusion of the label backport/1.16.

🚨

Warning automatic cherry-pick of commits failed. If the first commit failed,
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The person who merged in the original PR is:
@david-yu
This person should manually cherry-pick the original PR into a new backport PR,
and close this one when the manual backport PR is merged in.

merge conflict error: POST https://api.github.com/repos/hashicorp/consul/merges: 409 Merge conflict []

The below text is copied from the body of the original PR.

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Description

Removing Sentinel as a highlight from enterprise features as it only focuses as KV. Make it known that sentinel can be used with enterprise for KV in the KV docs.

Testing & Reproduction steps

Links

PR Checklist

• updated test coverage
• external facing docs updated
• appropriate backport labels added
• not a security concern

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Overview of commits

• 55d2b6d - 098a717 - 6832d89 - 3703d17 - ec073e7 - 26c356d - 5bea248 - 1ea87c8 - 15f5ab1 - aea5cc1 - 66036a2 - 5902321 - 9117803

[github-team-consul-core-pr-approver]

Auto approved Consul Bot automated PR