Update DB cleanup portion of drupal.md

[codyfishman]

The DB cleanup portion of this doc is recommended and is relevant to both D7 and D9.3+ Redis implementations.

Closes #

Summary

Doc Page Title - <Enter a one sentence summation of the pertinent changes (including not-yet-completed work) provided by this PR.>

Effect

The following changes are already committed:

Remaining Work and Prerequisites

The following changes still need to be completed:

• List any outstanding work here

Dependencies and Timing

• Other prerequisites that must be completed before merging this PR

Release:

• When ready
• After date: $DATE

---

Post Launch

Do not remove - To be completed by the docs team upon merge:

• Redirect /old-path/ => /new-path/ (if applicable)
• Include/exclude pages ^ respectively within docs search service provider (if applicable)

[stevector]

Is this a duplicate of #9051 ?

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[codyfishman]

Is this a duplicate of #9051 ?

@stevector this is a duplicate. I didn't realize @ccharlton had already submitted a PR.