Add documentation on how to add a new localization node in autoware

[SakodaShintaro]

Checklist

• I've read the contribution guidelines.
• I've searched other issues and no duplicate issues were found.
• I've agreed with the maintainers that I can plan this task.

Description

Add a new page under 'others' in the 'How to guide', and provide instructions on how to implement a new Localization node.
https://autowarefoundation.github.io/autoware-documentation/main/how-to-guides/#others

Purpose

While the content of Autoware's documentation is comprehensive, the information is not organized when viewed from a specific purpose (in this case, adding a Localization node). The goal of this document is to clarify the process and organize the information related to the workflow.

Possible approaches

Determine the steps necessary for implementing a new Localization node and write the information required at each step.

Definition of done

Write document and merge it.

[stale]

This pull request has been automatically marked as stale because it has not had recent activity.