histedit: remove extra histedit constructor call

In a previous commit we removed the extra histedit object instance being
constructed in --continue and --abort. The new --edit-todo missed this fix
though (which means the state object it produces doesn't have the locks on it).
It's not breaking anything now, but let's go ahead and clean that up before we
forget.

hgext/histedit.py

@@ -616,7 +616,6 b' def _histedit(ui, repo, state, *freeargs'
         state.read()
         state = bootstrapcontinue(ui, state, opts)
     elif goal == 'edit-plan':
-        state = histeditstate(repo)
         state.read()
         if not rules:
             comment = editcomment % (state.parentctx, node.short(state.topmost))