Remove unused anchors in case settings

[lcawl]

Relates to #5565 (review)

This PR removes extra anchors from the case settings pages. I checked in kibana, cloud, and integrations repos and they were not mentioned in the UIs there.

[github-actions]

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[mergify]

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

• v7.x is the label to automatically backport to the 7.x branch.
• v7./d./d is the label to automatically backport to the 7./d branch. /d is the digit

NOTE: backport-skip has been added to this pull request.

[nastasha-solomon]

lgtm - thank you for cleaning these files up!