Update Readme.md

Author: brauliodiez

hooks/15_Context/Readme.md

@@ -32,7 +32,7 @@ export const createDefaultUser = (): SessionContextProps => ({
 });
 
 export const SessionContext =
-  React.createContext < SessionContextProps > createDefaultUser();
+  React.createContext < SessionContextProps >(createDefaultUser());
 ```
 
 - This session context will expose a _provider_ (it will serve us to set the login name in the context), and a _consumer_ (that will let us consume the login name from the context at any point of the application).