Fix docs bundle size

The storybook documentation is taking up 4.5 MB which is huge. I'm guessing the problem is with assets or react-native-vector-icons.
We are actually not using the package on the web as the icons are coming from the `assets` folder inside `.storybook` which is approx 1 MB. It would be great if we can avoid importing native specific modules on web and reduce the bundle size.
Here is a [link](https://github.com/iamshadmirza/react-native-design-system/blob/master/.storybook/webpack.config.js) to webpack config file.

## Something that might help
Documentation was initially a separate repo [rnds_docs](https://github.com/iamshadmirza/rnds_docs). Everything is same in these two repos and rnds_docs is generating 2.43 MB of bundle size.
`rnds_docs` is actually a CRNA project using `@storybook/react` with `react-native-web`

## Requirement
According to the storybook build warning, the size limit should be `244 kb`. It would be great if we can bring this under 1 MB at least.

## Problem
Build size is 4.5 MB

Start with .storybook/webpack.config.js and inspect how the Storybook documentation build includes native modules and the .storybook/assets folder. Compare the result with the rnds_docs bundle and the Storybook build warning. Done means reducing the documentation bundle from 4.5 MB to under 1 MB.

Written by the indexing model from the issue text.