nghttpx: Fix te header field is duplicated when forwarding HTTP/2 backend

src/http2.cc

@@ -230,6 +230,7 @@ void copy_headers_to_nva(std::vector<nghttp2_nv> &nva, const Headers &headers) {
     case HD_KEEP_ALIVE:
     case HD_PROXY_CONNECTION:
     case HD_SERVER:
+    case HD_TE:
     case HD_TRANSFER_ENCODING:
     case HD_UPGRADE:
     case HD_VIA:

src/http2_test.cc

@@ -153,8 +153,8 @@ auto headers =
 void test_http2_copy_headers_to_nva(void) {
   std::vector<nghttp2_nv> nva;
   http2::copy_headers_to_nva(nva, headers);
-  CU_ASSERT(9 == nva.size());
-  auto ans = std::vector<int>{0, 1, 4, 5, 6, 7, 8, 9, 12};
+  CU_ASSERT(7 == nva.size());
+  auto ans = std::vector<int>{0, 1, 4, 5, 6, 7, 12};
   for (size_t i = 0; i < ans.size(); ++i) {
     check_nv(headers[ans[i]], &nva[i]);