Fix incorrect info about redirects

[internetisaiah]

Why are you making this change? (required)

There was some incorrect information about redirects throughout the contributing docs. I've also:

• Converted redirect troubleshooting steps to an include and added it to all relevant docs.
• Updated the headings for all YAML Meta Data sub-pages since code styling is now supported in in-page headings. I then re-ordered these sections alphabetically (which is why there are so many line changes. the vast majority of the content did not change).

Related PRs, issues, or features (optional)

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Feature release date (optional)

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[bre-fitzgerald]

lgtm!