[BUG] NaN in point animation when using spring animations

Describe the bug

When animating a <polygon> point list with a "spring" animation, at various points in the animation, the computed pointlist contains NaNs and throws console errors.

CodeSandbox reproduction of the bug

https://codesandbox.io/p/sandbox/pensive-khayyam-5mwd29?file=%2Fsrc%2FApp.js%3A9%2C68&workspaceId=5c31fde4-86cd-4353-99cd-cbe570ccc4aa

Steps to reproduce

1. Define an SVG with a polygon element.
2. Animate the points of the element, and use a spring animation.
3. Observe that you get a bunch of complaints about NaNs in your error console.

When the animation type is not "spring", the NaN errors are not thrown (though one "expected number, 'undefined'" message is thrown per polygon element).

Expected behavior

When an SVGPointList would produce NaNs, it should not incorrectly attempt to set the pointlist with NaNs on the element.

Environment details

Reproduced in Brave v 1.69.153 (Mozilla/5.0 (X11; Linux x86_64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/128.0.0.0 Safari/537.36)

Start with the linked CodeSandbox reproduction and trace the SVG polygon point-list animation path, especially the spring-animation handling. The fix is complete when spring animation no longer attempts to set polygon points containing NaN values and the related console errors no longer occur.