feat: separate component logic, add `<MotionGroup>` and tests

🔗 Linked issue

❓ Type of change

[ ] 📖 Documentation (updates to the documentation, readme or JSDoc annotations)
[x] 🐞 Bug fix (a non-breaking change that fixes an issue)
[ ] 👌 Enhancement (improving an existing functionality like performance)
[x] ✨ New feature (a non-breaking change that adds functionality)
[x] 🧹 Chore (updates to the build process or auxiliary tools and libraries)
[ ] ⚠️ Breaking change (fix or feature that would cause existing functionality to change)

📚 Description

This is both the continuation and replacement of #186, after a closer look it appeared that the <Motion> component broke by the dependency updates. As mentioned there, these changes resolve #45, and remove a type (SVGAttributes in MotoonProperties type) of which I'm not sure what the impact is on existing projects.

Since the <Motion> component isn't really documented at the moment I figured it would be safe to give it a refactor and see if some changes could be made. I separated its logic and added another component <MotionGroup>, this component is used when wanting to apply motion configuration on its child nodes/slots, which I removed from the <Motion> component, this makes it possible to no longer require is property as well. Please let me know if you have any feedback!

I spent some time to figure out how to test both the v-motion directive as well as the <Motion> component, hopefully we can expand on it more to keep things stable as we make changes.

📝 Checklist

[x] I have linked an issue or discussion.
[x] I have added tests (if possible).
[ ] I have updated the documentation accordingly.

vueuse / motion