Fix crash formatting error message

Author: ngoldbaum

setuptools/command/bdist_wheel.py

@@ -291,10 +291,16 @@ def _validate_py_limited_api(self) -> None:
             raise ValueError(f"py-limited-api must match '{PY_LIMITED_API_PATTERN}'")
 
         if sysconfig.get_config_var("Py_GIL_DISABLED"):
+            # sys.abiflags is only defined on POSIX
+            abiflags = getattr(sys, "abiflags", "")
+            if abiflags:
+                abinote = "(sys.abiflags={}). "
+            else:
+                abinote = ". "
             raise ValueError(
                 f"`py_limited_api={self.py_limited_api!r}` not supported. "
                 "`Py_LIMITED_API` is currently incompatible with "
-                f"`Py_GIL_DISABLED` ({sys.abiflags=!r}). "
+                f"`Py_GIL_DISABLED`{abinote}"
                 "See https://github.com/python/cpython/issues/111506."
             )