Implementing Add Course function in main

src/main/java/org/example/Main.java

@@ -31,6 +31,7 @@ public class Main {
                     break;
                 case 3:
                     System.out.println("Add Course selected");
+                    Course.addCourseFromUserInput("courseData.txt");
                     break;
                 case 4:
                     System.out.println("Delete Course selected");