Bump version to 1.3.1 in setup.py

Signed-off-by: Bofu Chen (bafu) <[email protected]>

Author: bafu

setup.py

@@ -10,7 +10,7 @@
 
 setup(
     name='cai',
-    version='v1.3.0',
+    version='v1.3.1',
     description='Content Authenticity Initiative Implementation.',
     long_description=long_description,
     long_description_content_type="text/markdown",