[docs] Rescue intentional line breaks

[mattstein]

The Issue

.editorconfig improvements in #4712 strip trailing spaces, which in Markdown removes two-space line endings ( ) than translate into <br> elements.

How This PR Solves The Issue

This removes the problematic trim_trailing_whitespace = true setting, re-adds two-space line endings that have since been stripped out of Markdown files, and fixes some other mangled spacing I noticed along the way.

The result allows Markdown to continue operating like someone would expect, without needing to resort to using <br> elements all over the place or unwittingly having their breaks stripped on save.

Note
After further discussion, this PR changed from originally inserting <br> elements to reverting trim_trailing_whitespace = true.

Manual Testing Instructions

Preview changes locally or inspect the automatic build.

Automated Testing Overview

n/a

Related Issue Link(s)

• Revert indentation specifier from editorconfig settings #4745
• Improve .editorconfig [skip ci] #4712

Release/Deployment Notes

n/a

[rfay]

Sorry if I'm being dense, but if trim_trailing_whitespace makes us dance around with <br> everywhere, and you have to know magic knowledge to accomplish that, then let's remove the trim_trailing_whitespace instead.

Normal markdown treats double linefeeds with respect. We'd rather have "normal" markdown.

Am I lost still?

[mattstein]

I brought this up here, reiterated again why trim_trailing_whitespace is useful here, and you suggested a PR to fix the Markdown and keep trim_trailing_whitespace here.

This is that PR.

The trim_trailing_whitespace setting is still enabled and those line breaks are stripped out. I don’t care what happens with the setting, I’m just trying to save the line breaks I added on purpose and I don’t want to keep circling the issue of what we do with that setting.

If you want me to drop trim_trailing_whitespace and turn those <br>’s back into double spaces again I can do that instead.

[rfay]

I'm the one that thinks trailing whitespaces do no harm. I apologize about this confusion, but I never thought this was a problem that needed solving. I guess we all think we're not being listened to. Do you think the trailing spaces is even a problem that needs solving? Does anybody but @gilbertsoft think it's a problem that needs solving?

[mattstein]

Do you think the trailing spaces is even a problem that needs solving?

Not in Markdown, no. But I can’t speak for the whole codebase or @gilbertsoft’s intentions—just defending my precious line breaks.

[mattstein]

@rfay Updated my approach here along with the description. Ready to review again.

[rfay]

Can we feel the pain receding?