Return a 404 response when no record is found

[MarcelEeken]

The JSON API specification says:

A server MUST respond with 404 Not Found when processing a request to fetch a single resource that does not exist

At the moment JSON API Resources returns a 200, with an empty data
object.

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[scottgonzalez]

@lgebhardt Is there a reason that show doesn't use find_by_key which would handle this error?

[lgebhardt]

@scottgonzalez Using find_by_key would result in an extra database call since we'd need to still get the included resources with find_resource_set.

[lgebhardt]

@MarcelEeken Thanks, this looks good to me.

[MarcelEeken]

@lgebhardt Thank you for approving, do you have any timeline when you expect this to be merged?