Exit with code 1 due to network error: ProtocolUnknownError

[fauust]

Investigate why we have very frequently the following error, PDF generation with python3 main.py --quiet.

[INFO] 08:10:03 Generating en(2716)
[INFO] 08:11:16 Merging HTML
[INFO] 08:15:07 Starting wk
Traceback (most recent call last):
  File "/srv/kb/mariadb-documentation/mariadb_pdf/main.py", line 22, in <module>
    main()
  File "/srv/kb/mariadb-documentation/mariadb_pdf/main.py", line 16, in main
    generate_full_pdf(lang_csv, Path(f"output_{lang}"), config)
  File "/srv/kb/mariadb-documentation/mariadb_pdf/pdf/generate_pdf.py", line 17, in generate_full_pdf
    generate_sub_pdf(kburls, dir_path, config, outline)
  File "/srv/kb/mariadb-documentation/mariadb_pdf/pdf/generate_pdf.py", line 33, in generate_sub_pdf
    wkhtmltopdf(f"{dir_path}/{config.html_path}", dir_path / config.pdf_path, config)
  File "/srv/kb/mariadb-documentation/mariadb_pdf/pdf/generate_pdf.py", line 59, in wkhtmltopdf
    pdfkit.from_file(
  File "/srv/kb/mariadb-documentation/mariadb_pdf/.venv/lib/python3.11/site-packages/pdfkit/api.py", line 51, in from_file
    return r.to_pdf(output_path)
           ^^^^^^^^^^^^^^^^^^^^^
  File "/srv/kb/mariadb-documentation/mariadb_pdf/.venv/lib/python3.11/site-packages/pdfkit/pdfkit.py", line 201, in to_pdf
    self.handle_error(exit_code, stderr)
  File "/srv/kb/mariadb-documentation/mariadb_pdf/.venv/lib/python3.11/site-packages/pdfkit/pdfkit.py", line 155, in handle_error
    raise IOError('wkhtmltopdf reported an error:\n' + stderr)
OSError: wkhtmltopdf reported an error:
Exit with code 1 due to network error: ProtocolUnknownError