Revert v2 api changes, we are v3 only now

Signed-off-by: Raul Gutierrez Segales <rgs@pinterest.com>

api/envoy/config/filter/http/gzip/v2/gzip.proto

@@ -20,7 +20,7 @@ option (udpa.annotations.file_status).package_version_status = FROZEN;
 // Gzip :ref:`configuration overview <config_http_filters_gzip>`.
 // [#extension: envoy.filters.http.gzip]
 
-// [#next-free-field: 12]
+// [#next-free-field: 11]
 message Gzip {
   enum CompressionStrategy {
     DEFAULT = 0;
@@ -95,9 +95,4 @@ message Gzip {
   // the fields `content_length`, `content_type`, `disable_on_etag_header` and
   // `remove_accept_encoding_header` are ignored.
   compressor.v2.Compressor compressor = 10;
-
-  // Value for Zlib's next output buffer. If not set, defaults to 4096.
-  // See https://www.zlib.net/manual.html for more details. Also see
-  // https://github.com/envoyproxy/envoy/issues/8448 for context on this filter's performance.
-  google.protobuf.UInt32Value chunk_size = 11 [(validate.rules).uint32 = {lte: 65536 gte: 4096}];
 }