Bump RiveSharp and SkiaSharp references

[csmartdalton]

The newer packages have emsdk 3.1.12 builds, which are compatible with Uno.Wasm.Bootstrap 7.x.

Fixes rive-app/rive-sharp#4

[michael-hawker]

Thanks! We can merge this in once the CI passes and @Arlodotexe approves - this should resolve what you need right?

@csmartdalton did we want to finish up #307 as well by moving to the DispatcherQueueTimer and then can bump the package version number?

[csmartdalton]

Thanks! We can merge this in once the CI passes and @Arlodotexe approves - this should resolve what you need right?

@csmartdalton did we want to finish up #307 as well by moving to the DispatcherQueueTimer and then can bump the package version number?

😱 I totally let that one slip!

Let's get it wrapped up.

[csmartdalton]

Looks like the build system tripped on SkiaSharp.Views 2.88.3, but we can land with 2.88.2 for now.

We will still have to get on SkiaSharp 2.88.3 before updating the bootstrapper, but RiveSharp is ready to go.

[Arlodotexe]

This is what we needed, big thanks @csmartdalton!