commands: use ctx.rev() instead of %d % ctx

Weaning off basectx.__int__.

Differential Revision: https://phab.mercurial-scm.org/D2429

mercurial/commands.py

@@ -860,7 +860,8 b' def bisect(ui, repo, rev=None, extra=Non'
                     transition = "bad"
                 state[transition].append(node)
                 ctx = repo[node]
-                ui.status(_('changeset %d:%s: %s\n') % (ctx, ctx, transition))
+                ui.status(_('changeset %d:%s: %s\n') % (ctx.rev(), ctx,
+                                                        transition))
                 hbisect.checkstate(state)
                 # bisect
                 nodes, changesets, bgood = hbisect.bisect(repo, state)