Add a rule and check for empty paragraphs

[pattonwebz]

This introduces a new rule to the JS scanner that can detect empty paragraph tags (or tags with whitespace inside of them, like spaces or returns).

@amberhinds I am going to need some copy/docs for this scan since it is new and there isn't something existing I can use or point to. An info URL and improved summary to show users in the details view and frontend highlighter. Picking which tags are suitable as well will be needed: https://www.deque.com/axe/core-documentation/api-documentation/#axecore-tags

[amberhinds]

When do you think this rule will be released @pattonwebz?

[pattonwebz]

@amberhinds it can be in the next release (next Tuesday) but if that's too soon we can probably do the week after? I do have one other new rule I will be adding as well that would need docs too.

I did write a quick summary myself that may be an acceptable starting point: https://github.com/equalizedigital/accessibility-checker/pull/591/files#diff-40652b9b45019a70bc2344f1b523a3220a53ef38d2d326f6821588666a1d2e7aR82

[amberhinds]

Tag: best-practice

This is going to be the documentation link: https://equalizedigital.com/accessibility-checker/empty-paragraph-tag/

I will finish that up in the morning. Let me know if you need anything else.