remove dead links

Author: ihabadham

.github/markdown-link-check-config.json

@@ -23,9 +23,6 @@
     },
     {
       "pattern": "^https://github\\.com/shakacode/react-webpack-rails-tutorial/blob/master/client/webpack\\.client\\.base\\.config\\.js"
-    },
-    {
-      "pattern": "^https://github\\.com/shakacode/react_on_rails/tree/master/lib/install/config/"
     }
   ],
   "replacementPatterns": [

docs/additional-details/upgrade-webpacker-v3-to-v4.md

@@ -5,8 +5,8 @@ _Note: This guide is outdated. The configuration files it references were remove
 The following steps can be followed to update a Webpacker v3.5 app to v4.
 
 1. Update the gem `webpacker` and the package `@rails/webpacker`
-1. Merge changes from the new default [.babelrc](https://github.com/shakacode/react_on_rails/tree/master/lib/install/config/.babelrc) to your `/.babelrc`. If you are using React, you need to add `"@babel/preset-react"`, to the list of `presets`.
-1. Copy the file [.browserslistrc](https://github.com/shakacode/react_on_rails/tree/master/lib/install/config/.browserslistrc) to `/`.
-1. Merge any differences between [config/webpacker.yml](https://github.com/shakacode/react_on_rails/tree/master/lib/install/config/webpacker.yml) and your `/config/webpacker.yml`.
+1. Merge changes from the new default `.babelrc` to your `/.babelrc`. If you are using React, you need to add `"@babel/preset-react"`, to the list of `presets`.
+1. Copy the file `.browserslistrc` to `/`.
+1. Merge any differences between `config/webpacker.yml` and your `/config/webpacker.yml`.
 
 Here is an [example commit of these changes](https://github.com/shakacode/react_on_rails-tutorial-v11/pull/1/files).