fix(nextjs): incorrect path when serving production builds (#14553)

closed #14507

Author: ndcunningham

packages/next/src/executors/server/server.impl.ts

@@ -47,7 +47,10 @@ export default async function* serveExecutor(
     parseTargetString(options.buildTarget, context.projectGraph),
     context
   );
-  const root = resolve(context.root, buildOptions.root);
+  const root = resolve(
+    context.root,
+    options.dev ? buildOptions.root : buildOptions.outputPath
+  );
   const config = await prepareConfig(
     options.dev ? PHASE_DEVELOPMENT_SERVER : PHASE_PRODUCTION_SERVER,
     buildOptions,