Add 'new' to Intl.ListFormat

[marcellamaki]

Summary

Description of the change(s) you made

At some point (I think during linting), I dropped the new from

const formatter = new Intl.ListFormat()

This caused an error when rendering any lists (reported in the accessibility criteria, but I suspect it would be anywhere multiple items can be selected).

Manual verification steps performed

1. Add a new item (I tried this for both .mp4 and .pdf as reported in the original issue @pcenov filed)
2. Select multiple accessibility criteria
3. Open View Detail - the content should display and there should be no console errors.

Screenshots (if applicable)

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Reviewer guidance

How can a reviewer test these changes?

See manual verification steps above

Are there any risky areas that deserve extra testing?

I think that we should wait to consider this "done" until the issue with the chips is resolved. While on the code side, I don't see how there would be any difference, I do think it would be good to double check and make sure there isn't anything I'm not accounting for in the lists.

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Contributor's Checklist

PR process:

• If this is an important user-facing change, PR or related issue the CHANGELOG label been added to this PR. Note: items with this label will be added to the CHANGELOG at a later time
• If this includes an internal dependency change, a link to the diff is provided
• The docs label has been added if this introduces a change that needs to be updated in the user docs?
• If any Python requirements have changed, the updated requirements.txt files also included in this PR
• Opportunities for using Google Analytics here are noted
• Migrations are safe for a large db

Studio-specifc:

• All user-facing strings are translated properly
• The notranslate class been added to elements that shouldn't be translated by Google Chrome's automatic translation feature (e.g. icons, user-generated text)
• All UI components are LTR and RTL compliant
• Views are organized into pages, components, and layouts directories as described in the docs
• Users' storage used is recalculated properly on any changes to main tree files
• If there new ways this uses user data that needs to be factored into our Privacy Policy, it has been noted.

Testing:

• Code is clean and well-commented
• Contributor has fully tested the PR manually
• If there are any front-end changes, before/after screenshots are included
• Critical user journeys are covered by Gherkin stories
• Any new interactions have been added to the QA Sheet
• Critical and brittle code paths are covered by unit tests

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Reviewer's Checklist

This section is for reviewers to fill out.

• Automated test coverage is satisfactory
• PR is fully functional
• PR has been tested for accessibility regressions
• External dependency files were updated if necessary (yarn and pip)
• Documentation is updated
• Contributor is in AUTHORS.md

[rtibbles]

Weird, I guess the error you saw for this previously was due to something else? Maybe the polyfill causing issues? Have confirmed that the constructor does indeed work like this.