fix(rustproxy-http): forward vectored write support in ShutdownOnDrop AsyncWrite wrapper

rust/crates/rustproxy-http/src/shutdown_on_drop.rs

@@ -50,6 +50,18 @@ impl<S: AsyncRead + AsyncWrite + Unpin + Send + 'static> AsyncWrite for Shutdown
         Pin::new(self.get_mut().inner.as_mut().unwrap()).poll_write(cx, buf)
     }
 
+    fn poll_write_vectored(
+        self: Pin<&mut Self>,
+        cx: &mut Context<'_>,
+        bufs: &[io::IoSlice<'_>],
+    ) -> Poll<io::Result<usize>> {
+        Pin::new(self.get_mut().inner.as_mut().unwrap()).poll_write_vectored(cx, bufs)
+    }
+
+    fn is_write_vectored(&self) -> bool {
+        self.inner.as_ref().unwrap().is_write_vectored()
+    }
+
     fn poll_flush(
         self: Pin<&mut Self>,
         cx: &mut Context<'_>,