smoke tests and cloudwatch alarms

Since titiler-cmr is now being used "in production" by Worldview, FIRMs and soon to be other VEDA instances, I would like to add some automated smoke tests to test a deployed instance with supported datasets and also some cdk for a cloudwatch alarm to email us given a certain number of 500 errors.

@hrodmn let me know if you have other thoughts and suggestions on this topic

**Update:** Based on below feedback I think we should:
- [ ] add logging that includes concept id
- [ ] add a dashboard that shows request by concept id
- [ ] add a metric for 500 errors
- [ ] connect that metric to slack
- [ ] I think smoke/integration tests could also be worthwhile