fix ext profile bug

src/components/user_card/user_card.vue

@@ -65,7 +65,7 @@
                   :title="$t('user_card.edit_profile')"
                 />
               </button>
-              <button
+              <a
                 v-if="isOtherUser && !user.is_local"
                 :href="user.statusnet_profile_url"
                 target="_blank"
@@ -75,7 +75,7 @@
                   class="icon"
                   icon="external-link-alt"
                 />
-              </button>
+              </a>
               <AccountActions
                 v-if="isOtherUser && loggedIn"
                 :user="user"