Separated out "Large target areas" into its own section within forms page

[nataliafitzgerald]

Separated out "Large target areas" into its own section and added to jump links menu. This makes more sense for the page hierarchy. There is still a future need to break this page up into separate pages but this update makes the most sense in the short term.

Additions

• Separated out "Large target areas" into its own section and added to jump links menu.

Removals

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Changes

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Testing

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Review

• @ielerol

Preview this PR without the whitespace changes

Screenshots

Notes

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Todos

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Checklist

• [ ] Changes are limited to a single goal (no scope creep)
• [ ] Code can be automatically merged (no conflicts)
• [ ] Code follows the standards laid out in the front end playbook
• [ ] Passes all existing automated tests
• [ ] New functions include new tests
• [ ] New functions are documented (with a description, list of inputs, and expected output)
• [ ] Placeholder code is flagged
• [ ] Visually tested in supported browsers and devices
• [ ] Project documentation has been updated (including the "Unreleased" section of the CHANGELOG)

[ielerol]

I think it should be possible to keep the longer name of the section lower on the page, and still use a short label in the jump links at the top. The link at the top would just look like [Large target areas](#checkboxes-and-radio-buttons-with-large-target-areas). The part after the hashtag has to match the actual words of the h2, but link text in brackets can be different. Not a big deal, but since the shortened title is a bit ambiguous I'd like to keep the longer title lower on the page.

[nataliafitzgerald]

@ielerol - Yep, that change makes sense. I went ahead and made the update and posted the commit. Can you take a look and merge if it looks good to go?