docs: document the use of the docker image

README.md

@@ -92,7 +92,7 @@ bin/satis-gitlab gitlab-to-config https://github.com  $SATIS_GITHUB_TOKEN --orgs
 bin/satis-gitlab build --skip-errors satis.json web
 ```
 
-(Note that GITHUB_TOKEN is required to avoid rate request limitation)
+(Note that SATIS_GITHUB_TOKEN is required to avoid rate request limitation)
 
 
 ### Mirror dependencies
@@ -123,6 +123,10 @@ Some command line options provide a basic customization options. You may also us
 
 [default-template.json](src/MBO/SatisGitlab/Resources/default-template.json)
 
+## Usage with docker
+
+See [docs/docker.md](docs/docker.md).
+
 ## Testing
 
 ```bash

docs/docker.md

@@ -9,6 +9,8 @@ Provide a docker image for satis-gitlab to :
 
 ## Build image
 
+> Alternative : use [ghcr.io/mborne/satis-gitlab:master](https://github.com/mborne/satis-gitlab/pkgs/container/satis-gitlab) instead of satis-gitlab bellow.
+
 ```bash
 docker build -t satis-gitlab .
 ```