fix content-length incorrectly set in proxyRequest (#532)

* fix content-length incorrectly set in proxyRequest

* Create mjwbenton.md

---------

Co-authored-by: conico974 <[email protected]>

Author: mjwbenton

.changeset/mjwbenton.md

@@ -0,0 +1,5 @@
+---
+"@opennextjs/aws": patch
+---
+
+fix content-length incorrectly set in proxyRequest

packages/open-next/src/core/routing/util.ts

@@ -181,6 +181,7 @@ function filterHeadersForProxy(
     "x-cache",
     "transfer-encoding",
     "content-encoding",
+    "content-length",
   ];
   Object.entries(headers).forEach(([key, value]) => {
     const lowerKey = key.toLowerCase();