net/http: fix typo in server commont

Change-Id: I5b04ba7e12eff933fc67eb7a1cbdfde536e4db88
Reviewed-on: https://go-review.googlesource.com/30722
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>

src/net/http/server.go

@@ -633,7 +633,7 @@ func newBufioReader(r io.Reader) *bufio.Reader {
 		br.Reset(r)
 		return br
 	}
-	// Note: if this reader size is every changed, update
+	// Note: if this reader size is ever changed, update
 	// TestHandlerBodyClose's assumptions.
 	return bufio.NewReader(r)
 }