animationName property does not conform to Property.AnimationName

[jonsadka]

Issue:
Per Styletron docs, keyframes takes the entire animation object to be set as animationName, however TypeScript throws an errors because animationName should be equal to Property.AnimationName | undefined per https://developer.mozilla.org/docs/Web/CSS/animation-name

Code Sandbox:
Repro case (FYI takes a minute to load):
https://codesandbox.io/s/staging-sea-flnccp?file=/src/App.tsx

Error:
Type '{ from: { marginLeft: string; }; to: { marginLeft: string; }; }' is not assignable to type 'AnimationName | undefined'.

[jonsadka]

cc @rtsao