[blob-service] Use S3 errors in HTTP endpoints

Summary:
Part of ENG-2398 - this diff changes the HTTP endpoints to use new S3 error types.

Depends on D8101

Test Plan: Mocked database functions to always return errors. Checked with postman that HTTP response codes are correct (400 for empty upload, 500 for others) and errors are logged correctly to stdout.

Reviewers: jon, varun, michal

Reviewed By: varun

Subscribers: ashoat, tomek

Differential Revision: https://phab.comm.dev/D8102