fix: Only request attachments if there are any

Signed-off-by: Julius Härtl <jus@bitgrid.net>

src/components/cards/CardCover.vue

@@ -65,7 +65,9 @@ export default {
 		cardId: {
 			immediate: true,
 			handler() {
+				if (this.$store.getters.cardById(this.cardId)?.attachmentCount > 0) {
 					this.fetchAttachments(this.cardId)
+				}
 			},
 		},
 	},