Bump Python requirement tenacity to 9.0.0

apistar/__init__.py

+# -*- coding: utf-8 -*-
+import warnings
+
+warnings.warn(
+    "The Arkindex API client no longer depends on APIStar. "
+    "Please update your `apistar` imports to use the `arkindex` package.",
+    FutureWarning,
+    stacklevel=2,
+)