add python3-requests for wazuh external integration

[Assylbek2002]

Some integrations like Slack, Telegram, Jira require the python3-requests module to send notifications.
However, this module is not included in the wazuh-manager image.

[Assylbek2002]

@teddytpc1 hi, can you review please?

[Assylbek2002]

@vcerenu can you review please?

[Assylbek2002]

@fcaffieri

[LaKishta]

We need this.

[vcerenu]

Hello @Assylbek2002

Thank you very much for your contribution!

We are aware that the official images do not include the dependencies needed by all the features. The reason is that the images are designed to be as lightweight as possible and avoid potential vulnerabilities.

If you need this dependency in your image, I encourage you to fork our repository and add it there, as you have all the necessary tools within our repository to generate your own images without problems. I regret not being able to include this requirement in our base image, but we try to avoid introducing vulnerabilities that we cannot manage and that not everyone needs.

We have our guide for building the images, which is quite simple:
https://documentation.wazuh.com/current/deployment-options/docker/build-docker-images-locally.html