Adjust lesson template (#704)

* Remove method `getId()` from all lessons as it defaults to the class name

* remove clean up endpoint

* remove unused class `RequestParameter`

* remove unused class `PluginLoadingFailure`

* Move `CourseConfiguration` to lesson package

* Add more content around the lesson template lesson and make it visible as a lesson in WebGoat

* Remove explicit invocation `trackProgress()` inside WebGoat framework so assignments only need to return an `AttackResult`

* Put original solution back as well for SQL string injection

* review comments

* Add

webgoat-lessons/cia/src/main/java/org/owasp/webgoat/cia/CIA.java

@@ -20,9 +20,4 @@ public class CIA extends Lesson {
     public String getTitle() {
         return "4.cia.title";//4th lesson in general
     }
-
-    @Override
-    public String getId() {
-        return "CIA";
-    }
 }

webgoat-lessons/cia/src/main/java/org/owasp/webgoat/cia/CIAQuiz.java

@@ -29,9 +29,9 @@ public class CIAQuiz extends AssignmentEndpoint {
         }
 
         if (correctAnswers == solutions.length) {
-            return trackProgress(success().build());
+            return success(this).build();
         } else {
-            return trackProgress(failed().build());
+            return failed(this).build();
         }
     }