fix: use supported redirect mode for Workers organization requests

tests/runtime/organization.capnp

@@ -0,0 +1,19 @@
+using Workerd = import "/workerd/workerd.capnp";
+
+const config :Workerd.Config = (
+  services = [
+    (name = "organization", worker = (
+      compatibilityDate = "2026-09-18",
+      globalOutbound = "organization-upstream",
+      modules = [
+        (name = "test.mjs", esModule = embed "organization-test.mjs"),
+        (name = "index.js", esModule = embed "../../src/index.js"),
+        (name = "org-context.js", esModule = embed "../../src/org-context.js")
+      ]
+    )),
+    (name = "organization-upstream", worker = (
+      compatibilityDate = "2026-09-18",
+      modules = [(name = "upstream.mjs", esModule = embed "organization-upstream.mjs")]
+    ))
+  ]
+);