Fix Vale issues for raketasks/cleanup.md

What does this MR do and why?

This MR condenses a wordy sentence in the documentation by removing the phrase "Note that."

Screenshots or screen recordings

How to set up and validate locally

1. Navigate to raketasks/cleanup.md
2. Ensure the phrase "Note that" has been removed from the sentence "This Rake task only removes the references to LFS files." on line 48.

MR acceptance checklist

This checklist encourages us to confirm any changes have been analyzed to reduce risks in quality, performance, reliability, security, and maintainability.

• I have evaluated the MR acceptance checklist for this MR.

Related to #387427 (closed)