Doc - Docker - fix installation instructions

Author: SimonMellerin

docs/content/getting-started/installation.md

@@ -121,11 +121,12 @@ volumes:
   pgdata:
 ```
 
-Then, copy the default configuration file from the vendor directory:
+Then, copy the default configuration file from the *DbToolsBundle* container:
 
 ```sh
 cd your_project_dir
-cp vendor/makinacorpus/db-tools-bundle/config/db_tools.standalone.sample.yaml db_tools.config.yaml
+
+docker compose cp dbtoolsbundle:/var/www/vendor/makinacorpus/db-tools-bundle/config/db_tools.standalone.sample.yaml db_tools.config.yaml
 ```
 
 Update this file to your needs. The only required parameter is `connections` in which you