Improve wazuh indexer package generation guide

[f-galland]

Description

This PR intends to make the Indexer's package generation guide more concise and easier to follow, by providing simple instructions and commands with a clearer format.

Checks

Docs building

• Compiles without warnings.

Code formatting and web optimization

• Uses three spaces indentation.
• Adds or updates meta descriptions accordingly.
• Updates the redirects.js script if necessary (check this guide).

Writing style

• Uses present tense, active voice, and semi-formal registry.
• Uses short, simple sentences.
• Uses bold for user interface elements, italics for key terms or emphasis, and code font for Bash commands, file names, REST paths, and code.

[QU3B1M]

Based on the changes proposed on the PR wazuh/wazuh-indexer#560, the package generation guide could be updated with something like this

.. Copyright (C) 2015, Wazuh, Inc.

.. meta::
   :description: Wazuh provides an automated way of building packages for the Wazuh components. Learn how to build your own Wazuh indexer package in this section of our documentation.

=============
Wazuh indexer
=============

Local packages generation
#########################

While official ``Wazuh Indexer`` packages are generated in a GitHub Actions pipeline, packages can also be compiled using a docker container.

.. contents:: Table of contents:
   :depth: 2
   :local:

.. raw:: html

  <div class="accordion-section open">

Pre-requisistes
===============

1. Clone the ``Wazuh Indexer`` GitHub repository and switch to the ``v|WAZUH_CURRENT|`` tag:

.. code:: console

   git clone https://github.com/wazuh/wazuh-indexer/
   git checkout v|WAZUH_CURRENT|

2. Bring the docker environment up:

.. code:: console

   cd wazuh-indexer/docker/builder
   docker build -t wazuh-indexer-builder .
   cd ../..

Build the wazuh-indexer package
=======================

A basic package including only the ``Wazuh Indexer`` engine without extra plugin is generated first.

1. Run the package build process:


.. code:: console

   docker run --rm -v ./artifacts/dist:/home/indexer/artifacts wazuh-indexer-builder

Environment Variables
=====================

You can customize the build process by setting the following environment variables:

- ``INDEXER_BRANCH``: The branch to use for the Wazuh Indexer (default: ``master``).
- ``INDEXER_PLUGINS_BRANCH``: The branch to use for the Wazuh Indexer plugins (default: ``master``).
- ``INDEXER_REPORTING_BRANCH``: The branch to use for the Wazuh Indexer reporting (default: ``master``).
- ``REVISION``: The revision number for the build (default: ``0``).
- ``IS_STAGE``: Whether the build is a staging build (default: ``false``).
- ``DISTRIBUTION``: The distribution format for the package (default: ``tar``).
- ``ARCHITECTURE``: The architecture for the package (default: ``x64``).

Example usage with custom environment variables

.. code:: console

   docker run --rm -e INDEXER_BRANCH="5.0.0" -e INDEXER_PLUGINS_BRANCH="5.0.0" -e INDEXER_REPORTING_BRANCH="5.0.0" -v ./artifacts/dist:/home/indexer/artifacts wazuh-indexer-builder