chore: document docker deployment for AGW

[lucaaamaral]

chore: document docker deployment for AGW

Problem

Current documentation points to fab and vagrand deployment, which might be outdated. The ongoing approach of reorganizing the documentation (#18) aims to ease readability and maintenance of the documentation structure.

Solution

Creating individual files showing the process to set up each Magma component is required in this scenario.
This issue aims to create a file under the readmes/deployment directory containing documentation on how to set up Magma AGW on a docker environment.

Non-goals

Anything specifically excluded from the concept

[lucaaamaral]

Assigned to @AndrewMbugua