webpack HtmlWebpackPlugin 插件如何忽略jsp标签？

Question

webpack配置

new HtmlWebpackPlugin({

      inject: true,

      minify: {

        ignoreCustomFragments: [ /\${[a-zA-Z]*?}/],

      },

      template: paths.appHtml

    }),

html

<script>

    var a="${a}";

    var b="${b}";

</script>

报错

Template execution failed: ReferenceError: a is not defined

请问要怎么配置才能够让插件忽略${}