Add message explaining partial recovery

lms/templates/instructor/staff_grading.html

@@ -30,6 +30,13 @@
             "to restore their visibility. Rest assured, no student "
             "data has been lost.")}
     </b>
+    <br>
+    <b>
+        ${_("We have recovered the majority of student responses. "
+            "Those responses submitted while the issue was active are "
+            "temporarily unavailable, but we are working on restoring "
+            "them, and they should be visible again shortly.")}
+    </b>
 </div>
 <br>
 <hr>

lms/templates/open_ended_problems/combined_notifications.html

@@ -24,6 +24,13 @@
                     "to restore their visibility. Rest assured, no student "
                     "data has been lost.")}
             </b>
+            <br>
+            <b>
+                ${_("We have recovered the majority of student responses. "
+                    "Those responses submitted while the issue was active are "
+                    "temporarily unavailable, but we are working on restoring "
+                    "them, and they should be visible again shortly.")}
+            </b>
         </div>
         <br>
         <hr>

lms/templates/open_ended_problems/open_ended_flagged_problems.html

@@ -27,6 +27,13 @@
                     "to restore their visibility. Rest assured, no student "
                     "data has been lost.")}
             </b>
+            <br>
+            <b>
+                ${_("We have recovered the majority of student responses. "
+                    "Those responses submitted while the issue was active are "
+                    "temporarily unavailable, but we are working on restoring "
+                    "them, and they should be visible again shortly.")}
+            </b>
         </div>
         <br>
         <hr>

lms/templates/open_ended_problems/open_ended_problems.html

@@ -24,6 +24,13 @@
                     "to restore their visibility. Rest assured, no student "
                     "data has been lost.")}
             </b>
+            <br>
+            <b>
+                ${_("We have recovered the majority of student responses. "
+                    "Those responses submitted while the issue was active are "
+                    "temporarily unavailable, but we are working on restoring "
+                    "them, and they should be visible again shortly.")}
+            </b>
         </div>
         <br>
         <hr>

lms/templates/peer_grading/peer_grading.html

@@ -23,6 +23,13 @@ criteria.{end_li_tag}
                     "to restore their visibility. Rest assured, no student "
                     "data has been lost.")}
             </b>
+            <br>
+            <b>
+                ${_("We have recovered the majority of student responses. "
+                    "Those responses submitted while the issue was active are "
+                    "temporarily unavailable, but we are working on restoring "
+                    "them, and they should be visible again shortly.")}
+            </b>
         </div>
         <br>
         <hr>