fix: get rid of warning for unused var

src/in_queue.liq

@@ -93,6 +93,7 @@ server.register(namespace = source.id(input_queue_0),
             log("Rolling #{t} seconds")
             t = float_of_string(default=0.,t)
             ret = source.seek(input_queue_0, t)
+            ignore(ret)
             "OK"
         end
     )
@@ -108,6 +109,7 @@ server.register(namespace = source.id(input_queue_1),
             log("Rolling #{t} seconds")
             t = float_of_string(default=0.,t)
             ret = source.seek(input_queue_1, t)
+            ignore(ret)
             "OK"
         end
     )