chore(build): refactoring makefile for better usability and introducing a default help target (#2930)

docs/versioned_docs/version-7.8.x/community/contribution.md

@@ -68,11 +68,22 @@ For starting oauth2-proxy locally open the debugging tab and create the `launch.
 
 Before you can start your local version of oauth2-proxy, you will have to use the provided docker compose files to start a local upstream service and identity provider. We suggest using [httpbin](https://hub.docker.com/r/kennethreitz/httpbin) as your upstream for testing as it allows for request and response introspection of all things HTTP.
 
-Open a terminal and switch to the `contrib/local-environment` directory.
+Inside the `contrib/local-environment` directory you can use the `Makefile` for
+starting different example setups:
 
-- Dex as your IdP: `docker compose -f docker-compose.yaml up dex etcd httpbin`
-- Keycloak as your IdP: `docker compose -f docker-compose-keycloak.yaml up keycloak httpbin`
+- Dex as your IdP: `make up` or `make down`
+- Dex as your IdP using the alpha-config: `make alpha-config-up`
+- Keycloak as your IdP: `make keycloak-up`
+- Dex as your IdP & nginx reverse proxy: `make nginx-up`
+- and many more...
 
-The username for both is `admin@example.com` and password is `password`.
+Check out the `Makefile` to see what is available.
+
+The username and password for all setups is usually `admin@example.com` and `password`.
+
+The docker compose setups expose the services with a dynamic reverse DNS resolver: localtest.me
+
+- OAuth2-Proxy: http://oauth2-proxy.localtest.me:4180
+- Upstream: http://httpbin.localtest.me:8080
+- Dex: http://dex.localtest.me:4190
 
-Start oauth2-proxy from the debug tab and open http://oauth2-proxy.localtest.me:4180/ for testing.