Course catalog: fix incoherence on user unsubscribe call so that it works in the catalog and also in other parts -refs BT#20594

main/auth/courses.php

@@ -49,7 +49,7 @@ switch ($action) {
 
         if (!empty($_GET['sec_token']) && $ctok == $_GET['sec_token']) {
             $auth = new Auth();
-            $result = $auth->remove_user_from_course($_GET['unsubscribe']);
+            $result = $auth->remove_user_from_course($_GET['course_code']);
             if ($result) {
                 Display::addFlash(
                     Display::return_message(get_lang('YouAreNowUnsubscribed'), 'success')

main/auth/sort_my_courses.php

@@ -223,7 +223,7 @@ function generateUnsubscribeForm(string $courseCode, string $secToken): string
     );
     $form->addHidden('action', 'unsubscribe');
     $form->addHidden('sec_token', $secToken);
-    $form->addHidden('unsubscribe', $courseCode);
+    $form->addHidden('course_code', $courseCode);
     $form->addButton('unsub', get_lang('Unsubscribe'));
 
     return $form->returnForm();

main/inc/lib/course.lib.php

@@ -5425,7 +5425,7 @@ class CourseManager
                 $my_course['unsubscribe_button'] = Display::url(
                     get_lang('Unreg').' '.
                     Display::returnFontAwesomeIcon('sign-out'),
-                    api_get_path(WEB_CODE_PATH).'auth/courses.php?action=unsubscribe&unsubscribe='.$courseCode
+                    api_get_path(WEB_CODE_PATH).'auth/courses.php?action=unsubscribe&=course_code'.$courseCode
                     .'&sec_token='.$stok.'&category_code='.$categoryCode,
                     [
                         'class' => 'btn btn-danger btn-sm',