FixTypo - Fix typo in various lesson documentations

src/main/resources/lessons/lessontemplate/documentation/lesson-template-attack.adoc

@@ -22,7 +22,7 @@ public class SampleAttack extends AssignmentEndpoint { // <3>
             //return failed(this).feedback("lesson-template.sample-attack.failure-2").build();
         }
 
-        //overly simple example for success. See other existing lesssons for ways to detect 'success' or 'failure'
+        //overly simple example for success. See other existing lessons for ways to detect 'success' or 'failure'
         if (secretValue.equals(param1)) {
             return success(this) // <7>
                     .output("Custom Output ...if you want, for success")