Update external injected item specs for metadata

Co-authored-by: Clara Muller <[email protected]>

Author: ben-kalmus

specs/composition-full/common/params/Composition.yml

@@ -46,17 +46,16 @@ externalInjectedItem:
     objectID:
       type: string
     metadata:
-      $ref: '#/injectedItemMetadata'
-  description: |
-    An objectID injected into an external source.
+      type: object
+      additionalProperties: true
+      description: |
+        User-defined key-values that will be added to the injected item in the response.
+        This is identical to Hits metadata defined in Composition or Composition Rule,
+        with the benefit of being set at runtime.
+      example: {'my-field': 'my-value'}
   required:
     - objectID
+  description: |
+    An objectID injected into an external source.
   example: {'objectID': 'my-object-1', 'metadata': {'my-field': 'my-value'}}
 
-injectedItemMetadata:
-  type: object
-  additionalProperties: true
-  description: |
-    User defined key-values that will be added to injected item in the response.
-    This is identical to Hits metadata which is defined in Composition or Composition Rule, with the benefit of being set at runtime.
-  example: {'my-value': 'my-field'}