hindi translation of about page and remaining parts of p5.js

[takshittt]

This pull request adds support for Hindi translations across various UI components of the p5.js Web Editor especially the 'about' page.

I have verified that this pull request:

• has no linting errors (npm run lint)
• has no test errors (npm run test)
• is from a uniquely-named feature branch and is up to date with the develop branch.
• is descriptively named and links to an issue number, i.e. #3485

[yugalkaushik]

LGTM.

[raclim]

Thanks for working on this @takshittt and thanks @yugalkaushik for verifying!

I think this PR seems to be addressing missing translations in the Keyboard Shortcuts modal rather than the About page, which is the original issue, so I removed the line in the description pertaining to that.

I think this is overall a positive change, so even though it doesn't touch a specific issue we can merge this in!