404's when fetching .eml files (from Action Mailbox)

## Bug report for Cloudinary Ruby SDK
The issue persists on https://rubygems.org/gems/cloudinary 2.4

## Describe the bug in a sentence or two.
Sometimes I get HTTP 404 when trying to fetch a .eml file (but the file exist in Cloudinary)

Initially reported in https://github.com/cloudinary/cloudinary_gem/issues/555

## Issue Type (Can be multiple)
- [ ] Build - Cannot install or import the SDK
- [ ] Performance - Performance issues
- [x] Behaviour - Functions are not working as expected (such as generate URL)
- [ ] Documentation - Inconsistency between the docs and behaviour
- [ ] Other (Specify)

## Steps to reproduce
- Start a new Rails project
- Set up [Action Mailbox](https://guides.rubyonrails.org/action_mailbox_basics.html) with Cloudinary as service
- Run the rails server, visit `/rails/conductor/action_mailbox/inbound_emails/` and create a few inbound emails
- You must see the error `Error performing ActionMailbox::RoutingJob` in the logs (it doesn't happen for all inbound emails, so be patient and keep adding them)

## Operating System
- [ ] Linux
- [ ] Windows
- [x] macOS
- [ ] All

## Environment and Libraries (fill in the version numbers)
- Cloudinary Ruby SDK version - 2.4
- Ruby Version - 3.1.7
- Rails Version - 7.1.5.2
- Other Libraries (ActiveStorage, etc) - activestorage = 7.1.5.2, actionmailbox = 7.1.5.2

## Repository

If possible, please provide a link to a reproducible repository that showcases the problem

Start by reproducing the failure through /rails/conductor/action_mailbox/inbound_emails/ and follow the Error performing ActionMailbox::RoutingJob path for inbound .eml files. Inspect the Cloudinary Active Storage integration and verify that all existing inbound emails can be fetched without HTTP 404 responses.

Vom Indexierungsmodell aus dem Issue-Text verfasst.