Check for a ending slach in the IIIF_SERVER_URL

[ksclarke]

If there isn't one, supply it. The sample env file has the form for the variable's value but it's reasonable to think not everyone will include the trailing slash, so check for it and add it if it's not found.

• UV resolves to the image server even if the configured IIIF_SERVER_URL doesn't end with a slash