[selectors-4] Fix typo

[kristoforsalmin]

I've replaced a word with more formal equivalent.

[tabatkins]

(Fine with it being merged, but that wasn't a typo - I spell the word that way intentionally. English spelling is terrible broken in some places.)

[frivoal]

https://www.youtube.com/watch?v=dz4Ps55Rx40&feature=youtu.be&t=65

[kristoforsalmin]

@tabatkins I'm sorry, didn't know that. I thought it'd be a good idea to use either of those forms consistently.

[bradkemper]

We also have “cough”, not “coff”. “Tough”, not “tuff”. “Rough”, not “ruff”. “Enough”, not “enuff”. “Thorough”, not “thurrow”. “Borough” spelled differently than “burrow”. “Bureau”, not “byurrow”. “Align”, not “uhlline”. And countless other words with non-phonetic confusing spellings.

Our specs should stick to English spelling as it is, not as we wish it was.

[tabatkins]

Spelling drifts with usage. ^_^ Like I said, I'm fine with it being merged, but I'm gonna keep using it myself.

[fantasai]

@racse1 As the other co-editor, I agree with @bradkemper and appreciate the fix.