fixing setup_github.sh to not break .env

Author: perfetti

setup_github.sh

@@ -3,6 +3,7 @@ export FRONTEND_BUILD_CONTEXT=https://${GH_TOKEN}@${FRONTEND_REPO_URL}#${FRONTEN
 export API_BUILD_CONTEXT=https://${GH_TOKEN}@${API_REPO_URL}#${API_REF}
 export BACKEND_BUILD_CONTEXT=https://${GH_TOKEN}@${BACKEND_REPO_URL}#${BACKEND_REF}
 
+echo "" > .env
 echo "FRONTEND_BUILD_CONTEXT=${FRONTEND_BUILD_CONTEXT}" >> .env
 echo "API_BUILD_CONTEXT=${API_BUILD_CONTEXT}" >> .env
 echo "BACKEND_BUILD_CONTEXT=${BACKEND_BUILD_CONTEXT}" >> .env