feat: enable traffic split plugin (#63)

diff --git a/charts/apisix/values.yaml b/charts/apisix/values.yaml
index e082bf9..641c13b 100644
--- a/charts/apisix/values.yaml
+++ b/charts/apisix/values.yaml
@@ -166,6 +166,7 @@
   - uri-blocker
   - wolf-rbac
   - zipkin
+  - traffic-split
 stream_plugins:
   - mqtt-proxy