Ported declaration model

Signed-off-by: Steve Springett <[email protected]>

Author: stevespringett

schema/2.0/cyclonedx-2.0.schema.json

@@ -69,6 +69,9 @@
     },
     "formulation": {
       "$ref": "model/cyclonedx-formulation-2.0.schema.json#/$defs/formulation"
+    },
+    "declarations": {
+      "$ref": "model/cyclonedx-declaration-2.0.schema.json#/$defs/declarations"
     }
 
   }