Allow reassignment of age variable

Author: fromonda

Sprint-1/2-mandatory-errors/1.js

@@ -5,4 +5,5 @@ age = age + 1;
 
 //The error message displayed by Node.js is:
 //Uncaught TypeError: Assignment to constant variable
-//The error happens because const creates a variable whose value cannot be reassigned.
+//The error happens because const creates a variable whose value cannot be reassigned.
+//To allow the value to change, the variable should be declared with let instead of const.