fix: Missing dependence packaging (#81)

* fix: Missing dependence packaging

* downgrade to 21.0
diff --git a/setup.cfg b/setup.cfg
index 37cf657..d195c25 100644
--- a/setup.cfg
+++ b/setup.cfg
@@ -76,6 +76,8 @@
     py4j~=0.10
     ruamel.yaml
     stmdency>=0.0.2
+    # 23.0 not support python 3.6
+    packaging>=21.3
 
 [options.packages.find]
 where=src