[flight recorder] Updated MatchState to have a member variable (pytorch#141297)

Summary: Without this change calling `str(MatchState.SOMETHING)` will cause exception.

Test Plan:
Can we add unittest somewhere?
Ensure `str(MatchState.FULLY_MATCHED)` and `str(MatchState.FULLY_MATCHED())` won't raise exception.

Differential Revision: D66321609

Pull Request resolved: pytorch#141297
Approved by: https://github.com/fduwjj

Author: c-p-i-o

tools/flight_recorder/components/types.py

@@ -74,7 +74,7 @@ def __call__(self, culprit: Optional[str] = None) -> "MatchState":
         return self
 
     def __str__(self) -> str:
-        details = f", {self.culprit}" if self.culprit else ""
+        details = f", {self.culprit}" if getattr(self, "culprit", None) else ""
         return f"Error type: {self.name}{details}"