test: Update build setup

extra/development.md

@@ -0,0 +1,39 @@
+## Development
+
+Overcommit can be used to ensure that Conventional commits are good.
+
+### Dev setup
+
+There 2 ways to interact with this project:
+
+1) Using Docker:
+
+```sh
+# Run rails server on the dummy app (=> http://localhost:3000 to access to ActiveAdmin):
+make up
+# Enter in a Rails console (with the dummy app started):
+make console
+# Enter in a shell (with the dummy app started):
+make shell
+# Run the linter on the project (with the dummy app started):
+make lint
+# Run the test suite (with the dummy app started):
+make specs
+# Remove container and image:
+make cleanup
+# To try different versions of Ruby/Rails/ActiveAdmin:
+RUBY=3.2 RAILS=7.1.0 ACTIVEADMIN=3.2.0 make up
+# For more commands please check the Makefile
+```
+
+2) With a local setup:
+
+```sh
+# Dev setup (set the required envs):
+source extra/dev_setup.sh
+# Install dependencies:
+bundle update
+# Run server (or any command):
+bin/rails s
+# To try different versions of Rails/ActiveAdmin edit extra/dev_setup.sh
+```