flashproxy writes temporary certificate files outside of TOR_PT_STATE_LOCATION
flashproxy/keys.py uses tempfile.NamedTemporaryFile without the dir
argument, meaning that files will be saved to some system-wide temporary directory. Even though the files are immediately deleted, we should not write anything outside of TOR_PT_STATE_LOCATION.
Behavior changed in 1e541947c32f8d390b5df1cc1c42928e7c058dd5. Before that, the get_state_dir
function was used to find out where to save the temporary file.