add jsx-ignore option to no-magic-numbers rule

[lizzzp1]

PR checklist

• Addresses an existing issue: Suggestion for no-magic-numbers #4412
• New feature, bugfix, or enhancement
  • Includes tests
• Documentation update

Overview of change:

Attempts to add an option to ignore jsx and leaves default as is.

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

First PR in here, I may have missed some things. :)
Feedback appreciated.

CHANGELOG.md entry:

[new-rule-option] added jsx-ignore option to no-magic-numbers rule

[palantirtech]

Thanks for your interest in palantir/tslint, @lizzzp1! Before we can accept your pull request, you need to sign our contributor license agreement - just visit https://cla.palantir.com/ and follow the instructions. Once you sign, I'll automatically update this pull request.

[JoshuaKGoldberg]

Exciting!, but needs some structural changes.

[JoshuaKGoldberg]

Looks like it's working! Some structural changes around option parsing, but the node/walking logic looks great.

[JoshuaKGoldberg]

Just the one nitpick. Leaving this unedited if you want the satisfaction of applying the code change yourself 😄 otherwise I'll just make it & merge this in next week. Thanks!

[JoshuaKGoldberg]

🙌 Thanks @lizzzp1! This looks great.