Gracefully handle a value that is not a string

[bsquizz]

Fixes:

  File "/iqe_venv/lib64/python3.11/site-packages/bonfire/processor.py", line 86, in _remove_untrusted_configs
    if not _is_trusted_config(data, regex, params, path):
           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/iqe_venv/lib64/python3.11/site-packages/bonfire/processor.py", line 50, in _is_trusted_config
    match = re.match(regex, value)
            ^^^^^^^^^^^^^^^^^^^^^^
  File "/usr/lib64/python3.11/re/__init__.py", line 166, in match
    return _compile(pattern, flags).match(string)
           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
TypeError: expected string or bytes-like object, got 'int'