Fix axs.utils.isLargeFont float issue (#345)

[timmhayes]

This fix should allow the isLargeFont function to correctly evaluate font sizes with decimals.

As it is now, a font sizes of 10pt can be evaluated as a large font because Chrome returns it as having a size of 13.333px, which the RegEx returns as 3333.

[googlebot]

Thanks for your pull request. It looks like this may be your first contribution to a Google open source project. Before we can look at your pull request, you'll need to sign a Contributor License Agreement (CLA).

📝 Please visit https://cla.developers.google.com/ to sign.

Once you've signed, please reply here (e.g. I signed it!) and we'll verify. Thanks.

---

• If you've already signed a CLA, it's possible we don't have your GitHub username or you're using a different email address. Check your existing CLA data and verify that your email is set on your git commits.
• If you signed the CLA as a corporation, please let us know the company's name.

[timmhayes]

I signed the CLA

[googlebot]

CLAs look good, thanks!