matches any valid UUID. This accepts v1, v2, v3, v4 and v5 UUIDs as FOLIO allows all of them,
but it excludes the Nil UUID
00000000-0000-0000-0000-000000000000 that usually serves as a
NullObject to be used for the Null Object Pattern.
A UUID has the form xxxxxxxx-xxxx-Mxxx-Nxxx-xxxxxxxxxxxx where the version M must be [1-5] and the variant N must be [89abAB]
raml-util repository has schemas/uuid.schema for UUID verification.
See also UUID at Wikipedia.