webpack でコンパイルしたファイルが読み込めていなかったのを修正

以下の修正を含む
* 互換性警告が出ていた webpack.config.js の [hash] を [contenthash] に置換
* 不要になった config/webpacker.yml を削除

.github/workflows/coverage.yaml

@@ -44,8 +44,8 @@ jobs:
         run: |
           cp config/database.yml.github_actions config/database.yml
           bin/rails db:setup
-      - name: Compile JS (webpack)
-        run: bin/yarn webpack
+      - name: Compile JavaScripts (webpack)
+        run: NODE_ENV=production bin/yarn webpack
       - uses: paambaati/codeclimate-action@v2.7.5
         env:
           CC_TEST_REPORTER_ID: 74e589ede57e23f089cbbd2eee75be23a93b5ace7b5cfce58213cd3f21447147

.github/workflows/test.yaml

@@ -53,7 +53,7 @@ jobs:
         run: |
           cp config/database.yml.github_actions config/database.yml
           bin/rails db:setup
-      - name: Compile JS (webpack)
-        run: bin/yarn webpack
+      - name: Compile JavaScripts (webpack)
+        run: NODE_ENV=production bin/yarn webpack
       - name: Run tests
         run: bin/rails test

webpack.config.js

@@ -13,7 +13,7 @@ module.exports = {
     application: path.resolve(__dirname, "app/javascript/packs/application.js"),
   },
   output: {
-    filename: isProd ? "[name]-[hash].js" : "[name].js",
+    filename: isProd ? "[name]-[contenthash].js" : "[name].js",
     path: path.resolve(__dirname, "public/packs"),
     publicPath: isProd ? "/packs/" : "//localhost:8080/packs/",
   },
@@ -40,7 +40,7 @@ module.exports = {
   plugins: [
     new CaseSensitivePathsPlugin(),
     new MiniCssExtractPlugin({
-      filename: isProd ? "[name]-[hash].css" : "[name].css",
+      filename: isProd ? "[name]-[contenthash].css" : "[name].css",
     }),
     new WebpackAssetsManifest({
       entrypoints: true,