Change docker-compose version to 3.8

Change-Id: If47cec165e915b5f2055e173af0e44e45a3b7431
diff --git a/cmd/hichipbridge/docker-compose.yml b/cmd/hichipbridge/docker-compose.yml
index c6b1489..d538fff 100644
--- a/cmd/hichipbridge/docker-compose.yml
+++ b/cmd/hichipbridge/docker-compose.yml
@@ -1,4 +1,4 @@
-version: "3.9"
+version: "3.8"
 services:
   bridge:
     image: "avm99963/hichipbridge:latest"