fix(config): make dynamic import work in config (#157)

Author: sapphi-red

packages/vite/src/node/config.ts

@@ -2215,6 +2215,8 @@ async function bundleConfigFile(
     sourcemapPathTransform(relative) {
       return path.resolve(fileName, relative)
     },
+    // we want to generate a single chunk like esbuild does with `splitting: false`
+    inlineDynamicImports: true,
   })
   await bundle.close()