This is to make it easier to implement support for exporting contexts in
3rd party code, or to create mocks in tests.
2 exemples where it simplify things:
- docker-app desktop-specific context decorator (which rewrites parts of
the docker context to simplify UX when using on Docker Desktop contexts)
- ucp for including a context in the connection bundle
Signed-off-by: Simon Ferquel <simon.ferquel@docker.com>