Explicitly set color to primary on v-switch

Vuetify 2 did this by default, but Vuetify 3 does not.

Author: mvandenburgh

web/src/components/DandisetsPage.vue

@@ -24,13 +24,15 @@
               v-model="showDrafts"
               label="Drafts"
               density="comfortable"
+              color="primary"
             />
           </v-list-item>
           <v-list-item>
             <v-switch
               v-model="showEmpty"
               label="Empty Dandisets"
               density="comfortable"
+              color="primary"
             />
           </v-list-item>
         </v-list>