remove deprecated plugins from readme (#1539)

Co-authored-by: Mike Evans <mike.evans at numical.com>

README.md

@@ -78,8 +78,6 @@ The `html-webpack-plugin` provides [hooks](https://github.com/jantimon/html-webp
  * [html-webpack-inline-svg-plugin](https://github.com/thegc/html-webpack-inline-svg-plugin) to inline SVGs in the resulting HTML file.
  * [html-webpack-exclude-assets-plugin](https://github.com/jamesjieye/html-webpack-exclude-assets-plugin) for excluding assets using regular expressions
  * [html-webpack-include-assets-plugin](https://github.com/jharris4/html-webpack-include-assets-plugin) for including lists of js or css file paths (such as those copied by the copy-webpack-plugin).
- * [script-ext-html-webpack-plugin](https://github.com/numical/script-ext-html-webpack-plugin) to add `async`, `defer` or `module` attributes to your `<script>` elements, or even inline them
- * [style-ext-html-webpack-plugin](https://github.com/numical/style-ext-html-webpack-plugin) to convert your `<link>`s to external stylesheets into `<style>` elements containing internal CSS
  * [html-webpack-injector](https://github.com/thearchitgarg/html-webpack-injector) to inject chunks in `head` or `body` (different locations ) of same html document.
  * [resource-hints-webpack-plugin](https://github.com/jantimon/resource-hints-webpack-plugin) to add resource hints for faster initial page loads using `<link rel='preload'>` and `<link rel='prefetch'>`
  * [preload-webpack-plugin](https://github.com/GoogleChrome/preload-webpack-plugin) for automatically wiring up asynchronous (and other types) of JavaScript chunks using `<link rel='preload'>` helping with lazy-loading