Description of problem:

Requesting blob that doesn't exist results in 500  from Pulp

How reproducible:

100% with changes in place for https://issues.redhat.com/browse/SAT-26533

Is this issue a regression from an earlier version:

Unsure, at least we've never tried this before.

Steps to Reproduce:

1. Make a GET request for a blob that doesn't exist
   1. "GET /v2/default_organization-precipitation-container_push_view-buttermilk_biscuits-arianna3/blobs/sha256:cd55268b264d4d04e2eb2a95520656af57b1a2f8f8924522c71ff8b6fbdff538 HTTP/1.1" 500 145 "-" "containers/5.30.0 (github.com/containers/image)"

Actual behavior:

A 500 is returned with a stack trace. See the GH issue for details (https://github.com/pulp/pulp_container/issues/1703)

Expected behavior: A proper error following the OCI registry spec should get returned.

Business Impact / Additional info:

Blocking https://issues.redhat.com/browse/SAT-26532