updated partially correct capa icon, accounting for lack of status label or…

updated partially correct capa icon, accounting for lack of status label or message on these problems. New icon used is an asterisk with the same green color.

common/lib/xmodule/xmodule/css/capa/display.scss

@@ -181,7 +181,7 @@ div.problem {
       }
 
       &.choicegroup_partially-correct {
-        @include status-icon($partiallycorrect, "\f00c");
+        @include status-icon($partiallycorrect, "\f069");
         border: 2px solid $partiallycorrect;
 
         // keep green for correct answers on hover. 
@@ -245,7 +245,7 @@ div.problem {
 
       // CASE: partially correct answer
       &.partially-correct {
-        @include status-icon($partiallycorrect, "\f00c");
+        @include status-icon($partiallycorrect, "\f069");
       }
 
       // CASE: incorrect answer
@@ -776,7 +776,7 @@ div.problem {
       }
 
       .status {
-        @include status-icon($partiallycorrect, "\f00c");
+        @include status-icon($partiallycorrect, "\f069");
       }
     }