added a button to toggle autosave submissions as well as a label to indicate current toggle status

app/views/exercises/external_users/statistics.html.slim

@@ -38,6 +38,17 @@ h1
           option data-submission=submission
             =index
           - index += 1
+  .bg-light.w-100.p-2.mb-4.align-items-center.d-flex.justify-content-between
+    - if @show_autosaves
+      span.pl-1.pb-1
+        i.fa.fa-info-circle.align-middle
+        small.mr-5.ml-1 = t('.toggle_status_on')
+      = link_to t('.toggle_autosave_off'), statistics_external_user_exercise_path(show_autosaves: false), class: "btn btn-outline-dark float-right btn-sm"
+    - else
+      span.pl-1.pb-1
+        i.fa.fa-info-circle.align-middle
+        small.mr-5.ml-1 = t('.toggle_status_off')
+      = link_to t('.toggle_autosave_on'), statistics_external_user_exercise_path(show_autosaves: true), class: "btn btn-outline-dark float-right btn-sm"
   #timeline
     .table-responsive
       table.table