Auto merge of #8551 - mrobinson:blessings, r=jgraham
Auto merge of #8551 - mrobinson:blessings, r=jgraham

Use blessings when possible for WPT UI

Use blessings when it is possible for the WPT UI and fall back to using
raw control characters. This also fixes a bug where the UI didn't work
correctly in iTerm.app. Remove the one line version of the UI, since it
is no longer used as the iTerm fallback.

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