Removed some PHP references from documentation.

[ismaelzsilva]

Trac ticket number

N/A

Branch description

Removed some unnecessary PHP references from documentation that would add complexity to a new user trying to understand the code.

I do consider that the next references does not add complexity but acts as useful examples. It would be nice thought, to generalize them by not taking an specific language as an example. I could not thing in way to improve it. Please feel free to make any recommendation.

https://docs.djangoproject.com/en/dev/howto/deployment/checklist/
https://docs.djangoproject.com/en/dev/ref/models/fields/
https://docs.djangoproject.com/en/dev/topics/security/
https://docs.djangoproject.com/en/dev/howto/error-reporting/

This ticket has been issued at DjangoCon 2024 - Vigo, at the Sprints Days.

Checklist

• This PR targets the main branch.
• The commit message is written in past tense, mentions the ticket number, and ends with a period.
• I have checked the "Has patch" ticket flag in the Trac system.
• I have added or updated relevant tests.
• I have added or updated relevant docs, including release notes if applicable.
• I have attached screenshots in both light and dark modes for any UI changes.

[LilyFoote]

Looks good to me overall.

[LilyFoote]

Without the examples I don't think it's clear what is meant by "cruft".