update opt4

setup.py

@@ -559,10 +559,10 @@ def get_version_add(sha: Optional[str] = None) -> str:
             if sha is None:
                 sha = get_sha(vllm_root)
             if (major, minor) >= ('2', '5'):
-                version = 'das.opt3.' + sha[:7]
+                version = 'das.opt4.' + sha[:7]
     else:
         if (major, minor) >= ('2', '5'):
-            version = 'das.opt3'
+            version = 'das.opt4'
 
 
     # dtk version