fix: fix rendering of empty paragraph tags in RTF

[eddieferrer]

• Sometimes contentful will add annoying empty paragraph tags in the rendered content from RTF's. This filters those out, but keeps empty paragraphs in the middle of the content

VUE-791

[mcstover]

I think this is a good fix for the issue. We will want to review some of our productionized pages though in Dev to see how they are affected by this change.

In particular all of the recent Cause work and the Homepage.

[eddieferrer]

I've been working with this fix locally for a little bit. Here are some example differences --
This fix on left, existing pages on right

Note - you can still manually add space in the RTF field by using a soft break (shift+enter)

[eddieferrer]

@mcstover @BoulderBrains see samples above ^

[mcstover]

Thanks @eddieferrer for the additional verification. We'll likely need to go through and smooth over some spacing with our verticalPadding configs in contentful.