Fix typo in tooltip documentation

[markhepburn]

Very minor change

[palantirtech]

Thanks for your interest in palantir/blueprint, @markhepburn! Before we can accept your pull request, you need to sign our contributor license agreement - just visit https://cla.palantir.com/ and follow the instructions. Once you sign, I'll automatically update this pull request.

[giladgray]

🎉 thanks @markhepburn!

[giladgray]

@markhepburn please sign the CLA when you have a chance and we'll get this merged and shipped!

[markhepburn]

@giladgray No problem; the cla site is timing out for me at the moment (is it still https://cla.palantir.com?), but when I notice it's back up I'll run through that. 👍

[giladgray]

@markhepburn 🤔 CLA site seems to load properly now. we are in the process of preparing the release so if you can close this out ASAP, we can get it in 1.34.0

[markhepburn]

@giladgray done!

[adidahiya]

This will be in the next patch release.