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/sql-injection/src/main/resources/html/SqlInjection.html

@@ -157,6 +157,7 @@
                         <option>'Smith</option>
                         <option>'</option>
                         <option>'Smith'</option>
+                        <option>Smith'</option>
                     </select></td>
                     <td>
                         <select name="operator">