fix(Session.attach): Remove refresh() call that fails after session killed

why: attach-session is a blocking interactive command where session state
can change arbitrarily during attachment, including being killed entirely.
Calling refresh() after such a command is semantically incorrect.
what:
- Remove self.refresh() call from Session.attach()

Fixes: tmux-python/tmuxp#1002

Author: tony

src/libtmux/session.py

@@ -329,8 +329,6 @@ def attach(
         if proc.stderr:
             raise exc.LibTmuxException(proc.stderr)
 
-        self.refresh()
-
         return self
 
     def kill(