Add usage entry for COB (#2810)

* Add usage entry for COB

COB has been failing the Dashboard's "Users" check because of missing metadata. I adapted the example from <https://obofoundry.org/principles/fp-009-users.html#examples> to provide one usage entry.

* Make YAML parser and tox happy

Author: jamesaoverton

ontology/cob.md

@@ -33,6 +33,14 @@ products:
   status: alpha
 repository: https://github.com/OBOFoundry/COB
 tracker: https://github.com/OBOFoundry/COB/issues
+usages:
+- description: Ontologies using COB terms
+  examples:
+  - description: List of ontologies using at least one COB term (See section entitled "Which ontologies use it?")
+    url: http://dashboard.obofoundry.org/dashboard/cob/dashboard.html
+  - description: List of ontologies using the term 'organism' (See section entitled "Ontologies that use the Class")
+    url: https://ontobee.org/ontology/COB?iri=http://purl.obolibrary.org/obo/COB_0000022
+  user: (multiple)
 activity_status: active
 ---