diagnosis: fix 'details' button style depending on theme

app/src/views/diagnosis/Diagnosis.vue

@@ -76,7 +76,7 @@
               </b-button>
               <b-button
                 v-if="item.details"
-                size="sm" variant="outline-dark" class="ml-lg-2 mt-2 mt-lg-0"
+                size="sm" :variant="'outline-' + (theme ? 'light' : 'dark')" class="ml-lg-2 mt-2 mt-lg-0"
                 v-b-toggle="`collapse-${report.id}-item-${i}`"
               >
                 <icon iname="level-down" /> {{ $t('details') }}
@@ -106,6 +106,8 @@
 </template>
 
 <script>
+import { mapGetters } from 'vuex'
+
 import api from '@/api'
 import { distanceToNow } from '@/helpers/filters/date'
 
@@ -122,6 +124,10 @@ export default {
     }
   },
 
+  computed: {
+    ...mapGetters(['theme'])
+  },
+
   methods: {
     formatReportItem (report, item) {
       let issue = false