Remove sprintf third party library

[ebogo1]

This is part of the effort to move third party dependencies to npm (or remove ones that are unneeded like sprintf - #9473

The changes here replace calls to sprintf with String.prototype.padStart(). This PR targets the npm staging branch because IE11 doesn't support this function.

[cesium-concierge]

Thanks for the pull request @ebogo1!

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• ❔ Changes to third party files were made.
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Reviewers, don't forget to make sure that:

• Cesium Viewer works.
• Works in 2D/CV.
• Works (or fails gracefully) in IE11.

[ebogo1]

Not sure if it'd make more sense to wrap these in a separate function - I tried a small wrapper around padStart to avoid all the calls to toString() but since there were only two use cases and both have different syntax it didn't look much cleaner.

[mramato]

I agree with your choice here, we don't really gain anything by string to add a helper function here.

[mramato]

Thanks @ebogo1!