chore: remove dead code

Author: Nirajn2311

mobile-app/lib/ui/views/learn/challenge/challenge_view.dart

@@ -306,7 +306,6 @@ class ChallengeView extends StatelessWidget {
               ..._panelIconButtons(
                 model,
                 challenge,
-                challengesCompleted,
                 block,
               ),
               Expanded(
@@ -337,18 +336,7 @@ class ChallengeView extends StatelessWidget {
                                     size: 30,
                                   ),
                         onPressed: model.hasTypedInEditor
-                            ? () async {
-                                if (model.showPanel &&
-                                    model.panelType == PanelType.pass) {
-                                  model.learnService.goToNextChallenge(
-                                    model.block!.challenges.length,
-                                    challengesCompleted,
-                                    challenge,
-                                    block,
-                                  );
-                                }
-                                model.runTests();
-                              }
+                            ? model.runTests
                             : null,
                         splashColor: Colors.transparent,
                         highlightColor: Colors.transparent,
@@ -556,7 +544,6 @@ class ChallengeView extends StatelessWidget {
   List<Widget> _panelIconButtons(
     ChallengeViewModel model,
     Challenge challenge,
-    int challengesCompleted,
     Block block,
   ) {
     return [