fix-boundary-scale: adds scaling to boundary Fixes #820

[cor1]

Proposed solution

This fixes #820 that I just filed. Basically when using a boundary element that has transform scale the bounding box is not what you expect.

Testing Done

Tested fix in my current project that uses this library, by modifying the index.js that is in the bundle with the same change.

[alexiz10]

Looks like the tsc GitHub action failed due to the usage of this.props.scale without first checking that it is undefined or providing an alternative value if it is.