pre-commit hook fails with log.showsignature=True

[jlec]

When using

[log]
    showsignature = true

I am running into

[jupytext] Reading ipynb/foo.ipynb in format ipynb
Traceback (most recent call last):
  File "/Users/kbpd943/.cache/pre-commit/repoqsz3404t/py_env-python3.12/bin/jupytext", line 8, in <module>
    sys.exit(jupytext())
             ^^^^^^^^^^
  File "/Users/kbpd943/.cache/pre-commit/repoqsz3404t/py_env-python3.12/lib/python3.12/site-packages/jupytext/cli.py", line 497, in jupytext
    exit_code += jupytext_single_file(nb_file, args, log)
                 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/Users/kbpd943/.cache/pre-commit/repoqsz3404t/py_env-python3.12/lib/python3.12/site-packages/jupytext/cli.py", line 649, in jupytext_single_file
    notebook, inputs_nb_file, outputs_nb_file = load_paired_notebook(
                                                ^^^^^^^^^^^^^^^^^^^^^
  File "/Users/kbpd943/.cache/pre-commit/repoqsz3404t/py_env-python3.12/lib/python3.12/site-packages/jupytext/cli.py", line 1125, in load_paired_notebook
    inputs, outputs = latest_inputs_and_outputs(
                      ^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/Users/kbpd943/.cache/pre-commit/repoqsz3404t/py_env-python3.12/lib/python3.12/site-packages/jupytext/pairs.py", line 90, in latest_inputs_and_outputs
    timestamp = get_timestamp(alt_path)
                ^^^^^^^^^^^^^^^^^^^^^^^
  File "/Users/kbpd943/.cache/pre-commit/repoqsz3404t/py_env-python3.12/lib/python3.12/site-packages/jupytext/cli.py", line 1069, in git_timestamp
    return float(git_ts_str)
           ^^^^^^^^^^^^^^^^^
ValueError: could not convert string to float: 'Good "git" signature for justin with ED25519 key SHA256:PEmlDyhy3y/rM/FP7NeSBbVaIcsEg/FATEYFX5buy3Q\n1731682599'