fix incorrect content in dist/cjs/package.json

Author: TaopaiC

dist/cjs/package.json

@@ -1 +1 @@
-{ type: commonjs }
+{ "type": "commonjs" }

rollup.config.js

@@ -18,7 +18,7 @@ export default [
         transformMixedEsModules: true,
         dynamicRequireTargets: ["**/js/src/static_dependencies/**/*.cjs"],
       }),
-      execute("echo { \"type\": \"commonjs\" } > ./dist/cjs/package.json") // this is needed to make node treat files inside dist/cjs as CJS modules
+      execute("echo '{ \"type\": \"commonjs\" }' > ./dist/cjs/package.json") // this is needed to make node treat files inside dist/cjs as CJS modules
     ],
     onwarn: ( warning, next ) => {
       if ( warning.message.indexOf('is implicitly using "default" export mode') > -1 ) return;