Add base line height on paragraphs to avoid constantly setting

[ashley-hebler]

What's this PR do?

Classes added (if any)

• t-space-base

Classes removed (if any)

• t-space-nospace

Why are we doing this? How does it help us?

This adds text formatting updates in story body and globally.

• Adds default line-height to p tags and converts line-heights to SASS variables
• Removes reliance on story body helper classes and scopes font rules to direct decedents of c-story-body instead. Add base line height on paragraphs to avoid constantly setting. We do this to keep plugin styles intact.

How should this be manually tested?

yarn dev

See: line-height variables
See: line-height variables

Does this introduce a breaking change where queso-ui is used in the wild? If so, is there a relevant branch/PR to accompany this release?

I'm going to test in the texastribune repo to be sure, but likely does not.

TODOs / next steps:

• Test 2.1.0-0 in donations (portal)
• Test 2.1.0-0 in texastribune