Fix manifest with experimental flag (#11192)

This ensures we don't attempt the manifests filtering behavior with this
experimental flag enabled as it is incompatible with it as we don't know
what to filter by at this point.

.changeset/brave-beds-call.md

@@ -0,0 +1,5 @@
+---
+"@vercel/next": patch
+---
+
+Fix manifest with experimental flag

packages/next/src/server-build.ts

@@ -270,10 +270,11 @@ export async function serverBuild({
     nextVersion,
     CORRECT_MIDDLEWARE_ORDER_VERSION
   );
-  const isCorrectManifests = semver.gte(
-    nextVersion,
-    CORRECTED_MANIFESTS_VERSION
-  );
+  // experimental bundling prevents filtering manifests
+  // as we don't know what to filter by at this stage
+  const isCorrectManifests =
+    !experimentalAllowBundling &&
+    semver.gte(nextVersion, CORRECTED_MANIFESTS_VERSION);
 
   let hasStatic500 = !!staticPages[path.posix.join(entryDirectory, '500')];