fix(docker): remove enable condition for beta image tagging

Author: cyk

.github/workflows/test_docker.yml

@@ -23,7 +23,7 @@ env:
   IMAGE_PUSH: 'true'
   IMAGE_TAGS_BETA: |
     type=ref,event=pr
-    type=raw,value=beta,enable={{is_default_branch}}
+    type=raw,value=beta               # 👈 去掉 enable 判断，强制所有情况都打上 beta 标签
 
 jobs:
   build_binary: