Frontend: Change :model-value to v-model in lightbox.vue photoprism#4777

Signed-off-by: Michael Mayer <michael@photoprism.app>

Author: lastzero

frontend/src/component/lightbox.vue

@@ -1,7 +1,7 @@
 <template>
   <v-dialog
     ref="dialog"
-    :model-value="visible"
+    v-model="visible"
     :scrollable="false"
     fullscreen
     scrim