Add lang attribute to the html element#1133

[Straw4yu]

Fixes #1133 (<=== Add issue number here)

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[gitpod-io]

[Straw4yu]

I think it's great

[leilayesufu]

Hii, @Straw4yu
This looks great to me, let’s wait for @TildaDares to give the final review

[TildaDares]

Amazing work @Straw4yu. Thank you!

[TildaDares]

Thanks for the reviews @leilayesufu!!

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[TildaDares]

Congratulations on merging your PR @Straw4yu 🎉🎉

[leilayesufu]

Anytime!! @TildaDares
Can I close the issue now?

[TildaDares]

Yes you can @leilayesufu. Thank you!