Use a variable to determine the target

The commit makes usage of a variable in the `config.mk` file to
determine the target configuration file dynamically based on the
environment. This change enhances the flexibility and efficiency of the
script, allowing for seamless configuration adjustments across different
environments.

scripts/govtool/config.mk

@@ -50,7 +50,7 @@ clear:
 $(output_dirs):
 	mkdir -p $@
 
-$(target_config_dir)/docker-compose.yml: $(template_config_dir)/docker-compose.yml.tpl $(target_config_dir)/
+$(docker_compose_file): $(template_config_dir)/docker-compose.yml.tpl $(target_config_dir)/
 	if [[ "$(env)" == "dev" ]]; then CSP_ALLOWED_HOSTS=",http://localhost"; else CSP_ALLOWED_HOSTS=; fi; \
 	sed -e "s|<DOMAIN>|$(domain)|g" \
 		-e "s|<DOCKER_USER>|$(docker_user)|g" \