Breaking: fix comma-dangle schema (fixes #13739)

[mrlorentx]

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What is the purpose of this pull request? (put an "X" next to an item)

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Fixes #13739

What changes did you make? (Give an overview)

Added additionalItems: false in order to allow specifying only 1 option.

Is there anything you'd like reviewers to focus on?

Please see #13166 for discussions regarding semver handling on this (breaking) change. A revert was made on the accepted PR, so this fix is pending a new major release

[eslint-deprecated]

Hi @JoakimoNilsson!, thanks for the Pull Request

The first commit message isn't properly formatted. We ask that you update the message to match this format, as we use it to generate changelogs and automate releases.

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[eslint-deprecated]

Hi @JoakimoNilsson!, thanks for the Pull Request

The first commit message isn't properly formatted. We ask that you update the message to match this format, as we use it to generate changelogs and automate releases.

• The length of the commit message must be less than or equal to 72

Read more about contributing to ESLint here

[eslint-deprecated]

Hi @JoakimoNilsson!, thanks for the Pull Request

The first commit message isn't properly formatted. We ask that you update the message to match this format, as we use it to generate changelogs and automate releases.

• The issue reference must be formatted as follows:

  If the pull request addresses an issue, then the issue number should be mentioned at the end. If the commit doesn't completely fix the issue, then use (refs #1234) instead of (fixes #1234).

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  Build: Update Travis to only test Node 0.10 (refs #734)
  Fix: Semi rule incorrectly flagging extra semicolon (fixes #840)
  Upgrade: Esprima to 1.2, switch to using comment attachment (fixes #730)
  

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[mdjermanovic]

Hi @JoakimoNilsson, thanks for the PR!

I converted this to draft to avoid accidental merging, as it's a breaking change so we'll wait for the next major release.

[mrlorentx]

Thank you @mdjermanovic! If there's anything I can do don't hesitate to ask!

[mdjermanovic]

@JoakimoNilsson the change looks good!

Could you please update the commit message to start with Breaking:?

It can be like the current PR title: Breaking: fix comma-dangle schema (fixes #13739)

Alternatively, we could change the commit message on merge.

[nzakas]

Let's just update on merge.

[mdjermanovic]

LGTM, thanks!

[snitin315]

LGTM