Translate `faq/extending.po`

[sofide]

This file is 75% translated and needs to reach 100%.

The rendered version of this file will be available at https://docs.python.org/es/3.13/faq/extending.html once translated.
Meanwhile, the English version is shown.

Current stats for faq/extending.po:

• Total entries: 66

• Entries that need work: 16 - (25%)

  • Fuzzy: 8
  • Untranslated: 8

Please, comment here if you want this file to be assigned to you and a member will assign it to you as soon as possible, so you can start working on it.

Remember to follow the steps in our Contributing Guide.