Fix log message when multiple tors try the same data directory

When a user launches two tor processes in the same data directory, they get these confusing logs:

Mar 29 17:45:08.000 [warn] It looks like another Tor process is running with the same data directory.  Waiting 5 seconds to see if it goes away.
Mar 29 17:45:13.000 [err] No, it's still there.  Exiting.
Mar 29 17:45:13.000 [err] set_options(): Bug: Acting on config options left us in a broken state. Dying. (on Tor 0.4.2.7 )
Mar 29 17:45:13.000 [err] Reading config failed--see warnings above.
Mar 29 19:55:41.000 [notice] Catching signal TERM, exiting cleanly.

Full logs: https://lists.torproject.org/pipermail/tor-relays/2020-March/018306.html

I don't think the bug log should be there.