docs(readme): update webpack compatibility note (#221)

Co-authored-by: Ricardo Gobbo de Souza <[email protected]>

Author: patrykszwed

README.md

@@ -12,7 +12,7 @@
 
 # eslint-webpack-plugin
 
-> This is eslint-webpack-plugin 3.0 which works only with webpack 5. For the webpack 4, see the [2.x branch](https://github.com/webpack-contrib/eslint-webpack-plugin/tree/2.x).
+> This version of eslint-webpack-plugin only works with webpack 5. For the webpack 4, see the [2.x branch](https://github.com/webpack-contrib/eslint-webpack-plugin/tree/2.x).
 
 This plugin uses [`eslint`](https://eslint.org/) to find and fix problems in your JavaScript code