Add Image.resolveAssetSource

[scottmas]

Add a web shim for Image.resolveAssetSource, as documented here https://reactnative.dev/docs/image#resolveassetsource

I was unable to get tests to run locally on my machine, but ran prettier and made sure that eslint and flow are happy.

[codesandbox-ci]

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Latest deployment of this branch, based on commit cd1d951:

Sandbox	Source
react-native-web-examples	Configuration

[quantizor]

I decided to fork this repo to apply the patch and make it available: https://www.npmjs.com/package/react-native-web-fork

The easiest way to use it is probably this package.json override:

{
  "overrides": {
    "react-native-web": "npm:react-native-web-fork"
  }
}

There are other patches applied as well, noted in the package README up top.

[scottmas]

Any updates on this?!? It should be an incredibly easy merge with zero downstream implications