chore(swagger): make it explicit when an object can have extra fields

To implement a strict API validation, let's annotate when extra fields
are actually expected.

Signed-off-by: Riccardo Mancini <[email protected]>

Author: Manciukic

src/firecracker/swagger/firecracker.yaml

@@ -482,6 +482,7 @@ paths:
           description: The MMDS data store JSON.
           schema:
             type: object
+            additionalProperties: true
         404:
           description: The MMDS data store content can not be found.
           schema:
@@ -1316,6 +1317,7 @@ definitions:
     type: object
     description:
       Describes the contents of MMDS in JSON format.
+    additionalProperties: true
 
   NetworkInterface:
     type: object