error message not consistent for the deleted datasets in catalog

[kvuppala]

https://catalog.data.gov/dataset/noaa-office-for-coastal-management-coastal-inundation-digital-elevation-model-new-york-city-wea

Above is an URL of a deleted dataset:

• when accessed through akamai we get "503 Service Unavailable" response code with a text message "File not found."" on the UI.
• BSP origins URL gives "500 Internal Server Error" response code
• Admin Catalog gives the correct "404 page not found" response code.

Akamai and Origin URLs to be corrected to provide the correct "404 page not found" response code.