Use counter-chip for absence-reason-chip

aleksis/apps/kolego/frontend/components/AbsenceReasonChip.vue

 <script>
+import CounterChip from "aleksis.core/components/generic/chips/CounterChip.vue";
+
 export default {
   name: "AbsenceReasonChip",
   props: {
@@ -17,7 +19,7 @@ export default {
       default: false,
     },
   },
-  extends: "v-chip",
+  extends: "CounterChip",
   computed: {
     text() {
       return this.short
@@ -29,7 +31,7 @@ export default {
 </script>
 
 <template>
-  <v-chip
+  <counter-chip
     :color="absenceReason.colour"
     :value="absenceReason.id"
     v-bind="$attrs"
@@ -51,5 +53,5 @@ export default {
         :width="2"
       />
     </v-avatar>
-  </v-chip>
+  </counter-chip>
 </template>