Corrected spelling "instanciate"

[jw4js]

Corrected spelling in the docs from "instanciate" to "instantiate"

[mention-bot]

@jw4js, thanks for your PR! By analyzing the history of the files in this pull request, we identified @Haypo, @birkenfeld, @bitdancer and @briancurtin to be potential reviewers.

[the-knights-who-say-ni]

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[jw4js]

Nevermind the CLA, would someone who has signed the CLA please fix that spelling error?

[bitdancer]

This should be backported, but I haven't learned how to do backports yet :(

[Mariatta]

I backported this to 3.5 and 3.6.

[bitdancer]

Thanks, Mariatta.