fix type of common name using futurize builtins

kedifa/test.py

@@ -17,6 +17,9 @@
 # See COPYING file for full licensing terms.
 # See https://www.nexedi.com/licensing for rationale and options.
 
+from builtins import str
+from builtins import range
+from builtins import object
 from io import BytesIO as StringIO
 import contextlib
 import datetime
@@ -193,7 +196,7 @@ class KedifaMixinCaucase(KedifaMixin):
         )
     self.cas = cas.split()
 
-    kedifa_key_pem, csr_file = self.generateCSR(common_name)
+    kedifa_key_pem, csr_file = self.generateCSR(str(common_name))
     out = StringIO()
     err = StringIO()
     caucase.cli.main(