chore: Remove unused dependency on favicons-webpack-plugin. (#1351)

This dependency depends on the `favicons` library which depends on
`sharp` which depends on a native library.

This complicates the build process as the library is built from source
because there's no binary available for my macOS Catalina
installation. As this is a common developer setup I expect others to
run into this issue as well, which is why I opted to fix this issue.

Co-authored-by: Danny Brown <danny.ri.brown@gmail.com>
Co-authored-by: Erik Ziegler <erik.sweed@gmail.com>

platform/viewer/.webpack/webpack.pwa.js

@@ -10,7 +10,6 @@ const BundleAnalyzerPlugin = require('webpack-bundle-analyzer')
 const { CleanWebpackPlugin } = require('clean-webpack-plugin');
 const CopyWebpackPlugin = require('copy-webpack-plugin');
 const ExtractCssChunksPlugin = require('extract-css-chunks-webpack-plugin');
-// const FaviconsWebpackPlugin = require('favicons-webpack-plugin');
 const HtmlWebpackPlugin = require('html-webpack-plugin');
 const { InjectManifest } = require('workbox-webpack-plugin');
 const TerserJSPlugin = require('terser-webpack-plugin');