Improve primitives.containers.PubResult __repr__ (#11722)

This is a cosmetic improvement.

qiskit/primitives/containers/pub_result.py

@@ -36,7 +36,7 @@ def __init__(self, data: DataBin, metadata: dict | None = None):
 
     def __repr__(self):
         metadata = f", metadata={self.metadata}" if self.metadata else ""
-        return f"{type(self).__name__}({self._data}{metadata})"
+        return f"{type(self).__name__}(data={self._data}{metadata})"
 
     @property
     def data(self) -> DataBin: