Fix invalid doc error

Another annoying case of Swagger fighting us

api/client-server/keys.yaml

@@ -62,19 +62,23 @@ paths:
                 additionalProperties:
                   type:
                     - string
-                    - type: object
-                      title: KeyObject
-                      properties:
-                        key:
-                          type: string
-                          description: The key, encoded using unpadded base64.
-                        signatures:
-                          type: object
-                          description: |-
-                            Signature for the device. Mapped from user ID to signature object.
-                          additionalProperties:
-                            type: string
-                      required: ['key', 'signatures']
+                    - object
+                    # XXX: We can't define an actual object here, so we have to hope
+                    # that people will look at the swagger source or can figure it out
+                    # from the other endpoints/example.
+                    # - type: object
+                    #   title: KeyObject
+                    #   properties:
+                    #     key:
+                    #       type: string
+                    #       description: The key, encoded using unpadded base64.
+                    #     signatures:
+                    #       type: object
+                    #       description: |-
+                    #         Signature for the device. Mapped from user ID to signature object.
+                    #       additionalProperties:
+                    #         type: string
+                    #   required: ['key', 'signatures']
                 example: {
                   "curve25519:AAAAAQ": "/qyvZvwjiTxGdGU0RCguDCLeR+nmsb3FfNG3/Ve4vU8",
                   "signed_curve25519:AAAAHg": {