simplify text for dropout popup

Co-authored-by: Johannes Wolf <[email protected]>

evap/student/templates/student_index_evaluate_or_drop.html

@@ -6,12 +6,7 @@
         <span slot="title">{% translate 'Did you drop this course?' %}</span>
         <span slot="question">
             {% blocktranslate %}
-                If you mark this course as dropped, you can still give feedback like normal, but your answers will only
-                be visible to contributors.
-            {% endblocktranslate %}
-            <br>
-            {% blocktranslate %}
-                You will not be able to vote for this course afterwards.
+                If you mark this course as dropped, you will still be able to provide feedback as usual. However, you can only submit the questionnaire once.
             {% endblocktranslate %}
         </span>
         <a class="btn btn-danger ms-2" slot="submit-group"