Bitbucket: Fix error in bitbucket cloud example (#656)

Replaces the parameter for the workspace request. The example tried to
get the workspaces by the workspace name. According to the
documentation they must be requested by the workspace slug. Workspace
name and slug are often the same, but in case they are different, the
example fails.

Author: jensvog

examples/bitbucket/bitbucket_cloud_oo.py

@@ -17,7 +17,7 @@
         break
 
 print()
-w = cloud.workspaces.get(w.name)
+w = cloud.workspaces.get(w.slug)
 p = w.projects.get(p.key)
 print("Project key " + p.key)
 for r in p.repositories.each():