Webpack 5 warnings

[ntucker]

• "Chunk.hasEntryModule: Use new ChunkGraph API" - webpack-fix-style-only-entries - Webpack 5 warnings fqborges/webpack-fix-style-only-entries#31
• "Compilation.assets will be frozen in future" - html-webpack-plguin: Webpack 5 "BREAKING CHANGE" warning jantimon/html-webpack-plugin#1501
• "<w> [webpack.cache.PackFileCacheStrategy/webpack.FileSystemInfo] Managed item [redacted]/anansi/node_modules/@babel/core/node_modules/@babel/template isn't a directory or doesn't contain a package.json"
• "[DEP_WEBPACK_WATCH_WITHOUT_CALLBACK] DeprecationWarning: A 'callback' argument need to be provided to the 'webpack(options, callback)' function when the 'watch' option is set. There is no way to handle the 'watch' option without a callback." [DEP_WEBPACK_WATCH_WITHOUT_CALLBACK] error when using --watch flag webpack/webpack-cli#1918

Dropping webpack 4:

• html-webpack-plugin v5 - drops v4 webpack support
• css-loader v5 - drops webpack 4 support
• terser-webpack-plugin v5 - drops webpack 4 support