feat: Add support for GRPC_ARG_ENABLE_HTTP_PROXY parameter

Signed-off-by: Antoine.orhant <[email protected]>

Author: keskydi

src/channel.rs

@@ -295,6 +295,15 @@ impl ChannelBuilder {
         );
         self
     }
+    
+    /// If set to zero, disables use of http proxies.
+    pub fn enable_http_proxy(mut self, num: i32) -> ChannelBuilder {
+        self.options.insert(
+            Cow::Borrowed(grpcio_sys::GRPC_ARG_ENABLE_HTTP_PROXY),
+            Options::Integer(num),
+        );
+        self
+    }
 
     /// Set default compression algorithm for the channel.
     pub fn default_compression_algorithm(mut self, algo: CompressionAlgorithms) -> ChannelBuilder {