Increase version.

PiperOrigin-RevId: 631169158

Author: psc-g

setup.py

@@ -51,7 +51,7 @@
 
 setup(
     name='dopamine_rl',
-    version='4.0.8',
+    version='4.0.9',
     description=dopamine_description,
     long_description=long_description,
     long_description_content_type='text/markdown',