Do not write except:, use except Exception instead

Follow the hacking: http://docs.openstack.org/developer/hacking.
Do not write except:, use except Exception: at the very least.
When catching an exception you should be as specific so you
don’t mistakenly catch unexpected exceptions.This patch is to
fix it.

Change-Id: Iefdc52e7ad87a51b79ac1fa1175f7b62e6d8eb4f
Closes-Bug: #1600714

barbicanclient/base.py

@@ -39,7 +39,7 @@ def validate_ref(ref, entity):
     try:
         _, entity_uuid = ref.rstrip('/').rsplit('/', 1)
         uuid.UUID(entity_uuid)
-    except:
+    except Exception:
         raise ValueError('{0} incorrectly specified.'.format(entity))
 
     return True

barbicanclient/tests/keystone_client_fixtures.py

@@ -236,7 +236,7 @@ class KeystoneClientFixture(testtools.TestCase):
 
         try:
             self.barbican.run(argv=argv)
-        except:
+        except Exception:
             self.fail('failed to delete secret')
 
     def test_v2_auth(self):