Correct docs for R6 classes

[olivroy]

See https://rstudio.github.io/chromote/reference/Chromote.html
There is a bug on the top of the page.

This correction is done to circumvent r-lib/roxygen2#1504

Edit: changes to the R files could be reverted once the issue is fixed.

[CLAassistant]

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[gadenbuie]

Thanks for pointing this out to us @olivroy. I understand this doesn't look as good as it possibly could, but it sounds like a fix will be applied upstream. As long as our documentation is still readable and functional, I'd prefer to just wait for the upstream fix at which point this will resolve itself.

[hadley]

@gadenbuie it's probably going to be a while until a fix gets into roxygen2, so I think you should merge this PR.

[gadenbuie]

Thank you @olivroy!

@wch or @hadley, I'll let you handle merging since you're actively working on chromote.

[olivroy]

Only need to redocument and this would be ok to go