Fixes #1158.

When a rerun times out and The Fuck cannot terminate a process due to psutil.AccessDenied, _kill_process logs the process executable. On sudo-owned processes, that executable lookup can also raise AccessDenied, which turns the timeout handling path into a traceback.

This keeps the timeout cleanup best-effort by falling back to a placeholder executable name when proc.exe() is denied, so the rerun path can return normally instead of crashing.

Verification:

• PYTHONPATH=. .venv/bin/python -m pytest tests/output_readers/test_rerun.py::TestRerun::test_kill_process_access_denied_when_exe_is_denied -q
• PYTHONPATH=. .venv/bin/python -m pytest tests/output_readers/test_rerun.py -q
• PYTHONPATH=. .venv/bin/python -m pytest tests/rules/test_apt_list_upgradable.py tests/rules/test_apt_upgrade.py -q
• PYTHONPATH=. .venv/bin/python -m pytest tests/output_readers -q
• .venv/bin/python -m py_compile thefuck/output_readers/rerun.py tests/output_readers/test_rerun.py
• .venv/bin/python -m flake8 thefuck/output_readers/rerun.py tests/output_readers/test_rerun.py
• git diff --check