MAINT: Add unit to schema

src/caoscrawler/cfood-schema.yml

@@ -135,6 +135,9 @@ cfood:
                   value:
                     description: Dictionary notation for variable values. Values can be given by a variable which is indicated by an initial "$". Use "$$" for setting values actually starting with a dollar sign.
                     type: string
+                  unit:
+                    description: The unit of this property. Units can be given by a variable which is indicated by an initial "$". Use "$$" for setting values actually starting with a dollar sign.
+                    type: string
                   collection_mode:
                     description: The collection mode defines whether the resulting property will be a single property or whether the values of multiple structure elements will be collected either into a list or a multiproperty.
                     enum: