Requests with names using uppercase letters lead to 404 responses instead of 400
Context
Found this in https://gitlab.com/gitlab-com-top-initiatives/free-saas-user-efficiency/free-saas/-/issues/93#note_1025026083. Not yet sure if this only applies to this API/endpoint, but there it happened for the recently introduced "get repository details" operation.
Problem
When using a repository path with upper case letters, the registry API is returning a 404 Not Found
response. According to the OCI spec (source), a repository name must be all lowercase letters, so this should have been rejected with a 400 Bad Request
instead.
Solution
Find out the extension of this issue and implement a solution.