make group's address field optional again

- reverts some changes in e4607567ce
- issue #27

src/views/Group/CreateView.vue

@@ -84,7 +84,7 @@
       <full-address-auto-complete
         :label="$t('Group address')"
         v-model="group.physicalAddress"
-        :is-required="true"
+        :is-required="false"
       />
 
       <div class="field">

src/views/Group/GroupSettings.vue

@@ -160,7 +160,7 @@
           v-model="currentAddress"
           :allowManualDetails="true"
           :hideMap="true"
-          :is-required="true"
+          :is-required="false"
         />
 
         <div class="flex flex-wrap gap-2 my-2">