Fixed usages of get_unique_id to free result

src/xmpp/bookmark.c

@@ -403,6 +403,7 @@ _send_bookmarks(void)
     xmpp_stanza_set_name(iq, STANZA_NAME_IQ);
     char *id = generate_unique_id("bookmarks_update");
     xmpp_stanza_set_id(iq, id);
+    free(id);
     xmpp_stanza_set_type(iq, STANZA_TYPE_SET);
 
     xmpp_stanza_t *query = xmpp_stanza_new(ctx);
@@ -479,4 +480,4 @@ bookmark_init_module(void)
     bookmark_get_list = _bookmark_get_list;
     bookmark_find = _bookmark_find;
     bookmark_autocomplete_reset = _bookmark_autocomplete_reset;
-}
+}