Fix secret/{id} response example

Fixes a warning that was shown;

    Warning: Other properties are defined at the same level as $ref at
    "#/paths/~1secrets~1{id}/get/responses/200/schema". They are IGNORED according
    to the JsonSchema spec

That resulted in the example not being
rendered in the documentation.

Signed-off-by: Sebastiaan van Stijn <github@gone.nl>

api/swagger.yaml

@@ -8242,7 +8242,8 @@ paths:
           description: "no error"
           schema:
             $ref: "#/definitions/Secret"
-            example:
+          examples:
+            application/json:
               ID: "ktnbjxoalbkvbvedmg1urrz8h"
               Version:
                 Index: 11