feat(back-api-core): clean up resources on shutdown

[spy4x]

https://cloud.google.com/blog/topics/developers-practitioners/graceful-shutdowns-cloud-run-deep-dive

process.on('SIGTERM', () => {
  console.log(`${pkg.name}: received SIGTERM`);
  redisClient.quit();
  prisma.quit()
  process.exit(0);
});