examples: replace all app.Run(iris.Addr(...)) with app.Listen just for the shake of simplicity, both are doing the same exact thing as it's described on the http listening first example.

Former-commit-id: d20afb2e899aee658a8e0ed1693357798df93462

_examples/orm/gorm/main.go

@@ -165,7 +165,7 @@ func main() {
 			"data": user.Serializer(),
 		})
 	})
-	app.Run(iris.Addr(":8080"), iris.WithoutServerError(iris.ErrServerClosed))
+	app.Listen(":8080", iris.WithoutServerError(iris.ErrServerClosed))
 }
 
 type patchParam struct {