Update JSXV4.md

Author: cristianoc

cli/JSXV4.md

@@ -79,7 +79,7 @@ React.createElement(Comp.make, {x, key: "7"})
 
 type props<'x, 'y, 'z> = {x: 'x, @optional y: 'y, @optional z: 'z}
 
-let make: (props<int, int, int>) => React.element
+props<int, int, int> => React.element
 ```
 
 Since an external is a function declaration, it follows the same rule.