[meta][several specs] Fix markup to not start lines with >

[tabatkins]

Per 6722380#commitcomment-24667401, several specs linebreak in the middle of a tag, starting the next line with the closing > character. This activates Bikeshed's new support for Markdown blockquotes, and results in some messed up HTML.

Tagging the relevant specs in labels, remove the spec from the labels when it's fixed and close the issue when they're all fixed.

[rachelandrew]

I'll fix multicol.

[frivoal]

Fixed the rest, and a few more place that had the same pattern.