Fix spelling mistakes that appear on the webapp

[JoelLefkowitz]

Some comments that get marked up into text on the webapp have grammar mistakes. Usually don't bother with spelling but this one caught my eye :)

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[JoelLefkowitz]

@mmalerba could you please review again?

[andrewseguin]

Thanks for your contribution - can you rebase this PR?

[JoelLefkowitz]

Thanks @andrewseguin, rebased it. How can I trigger the google-internal-tests workflow?

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