set type to props

Signed-off-by: Maxence Lange <maxence@artificial-owl.com>

src/components/PostAttachment.vue

@@ -24,7 +24,10 @@ export default {
 	},
 	mixins: [],
 	props: {
-		attachments: Array
+		attachments: {
+			type: Array,
+			default: Array
+		}
 	},
 	data() {
 		return {