net/http: fix typo in Response.Body's doc

Fixes #33453.

Change-Id: If0aa48f953633690884ddcff033b3be6d1d66443
Reviewed-on: https://go-review.googlesource.com/c/go/+/188541Reviewed-by: Emmanuel Odeke <emm.odeke@gmail.com>

src/net/http/response.go

@@ -66,7 +66,7 @@ type Response struct {
 	// The Body is automatically dechunked if the server replied
 	// with a "chunked" Transfer-Encoding.
 	//
-	// As of Go 1.12, the Body will be also implement io.Writer
+	// As of Go 1.12, the Body will also implement io.Writer
 	// on a successful "101 Switching Protocols" response,
 	// as used by WebSockets and HTTP/2's "h2c" mode.
 	Body io.ReadCloser