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.

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[timmhayes]

I signed the CLA

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