Typo in JSON-LD context for IIIF Authentication API 1.0 (and the draft version)

[lutzhelm]

The JSON-LD context files for IIIF Authentication API 1.0 and the draft version of the API both contain a typo, failureDescriptiom instead of failureDescription:

https://github.com/IIIF/api/blob/17629e12c6fa0327b6043bcdffa8c7f804d48edb/source/auth/1/context.json#L33-L35

https://github.com/IIIF/api/blob/17629e12c6fa0327b6043bcdffa8c7f804d48edb/source/auth/0/context.json#L33-L35