[DOCS] Scattered info on running jobs in containers #630
Description
Semaphore can run jobs in custom Docker containers, which is a way for organizations to bring their own pre-built environment. However it is close to impossible to discover this by browsing documentation.
Information is scattered in the following few places and does not show up easily in search:
- How to use it https://docs.semaphore.io/using-semaphore/pipelines#docker-environments
- How to use an image from a private registry https://docs.semaphore.io/using-semaphore/pipelines#docker-private
- Reference in yaml https://docs.semaphore.io/reference/pipeline-yaml#containers
Proposed solution is to start by re-composing the content to appear in the top-level Containers section.