API 404s if trailing slash is omitted from URL

[AdamWill]

Try this:

https://pdc.fedoraproject.org/rest_api/v1/compose-images/Fedora-26-20170705.0

Then try this:

https://pdc.fedoraproject.org/rest_api/v1/compose-images/Fedora-26-20170705.0/

That's pretty unhelpful! Also, I'm pretty sure it changed at some point, and PDC used to gracefully handle URLs with the trailing / omitted, because the code I wrote that's running into this issue has not changed since I wrote it (and thus never should have worked, if URLs without the trailing / had never worked).