Docs: Changed "language to avoid" to "usage list"

What does this MR do?

This MR updates the list of "Language to avoid" in the style guide and makes it a terms/usage list instead.

The idea is that the information is easier to find if it's categoried. At some point we hope to move this to a separate usage guide/terms list page.

Other changes:

• It puts the information in a table and alphabetizes it so it's easier to read.
• It removes the "Word usage clarifications" and "Point of view" sections.
• It uses bold because the italics was hard to read.

Related issues

Author's checklist (required)

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When applicable:

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