Added workaround for default enabled HTTP2 configuration

recipes/graceful-shutdown/grace/server.go

@@ -14,5 +14,14 @@ func main() {
 		return c.String(http.StatusOK, "Six sick bricks tick")
 	})
 
-	gracehttp.Serve(e.Server(":1323"))
+	// Get the http.Server
+	s := e.Server(":1323")
+
+	// HTTP2 is currently enabled by default in echo.New(). To override TLS handshake errors
+	// you will need to override the TLSConfig for the server so it does not attempt to valudate
+	// the connection using TLS as required by HTTP2
+	s.TLSConfig = nil
+
+	// Serve it like a boss
+	gracehttp.Serve(s)
 }