update comment, clarify the behaviour for reset

Author: ychebotarev

openapi/openapiv2.json

@@ -8181,7 +8181,7 @@
         },
         "restoreOriginal": {
           "type": "boolean",
-          "description": "If set, the activity options will be restored to the default.\nDefault options are then options activity was created with.\nThey are part of the first SCHEDULE event."
+          "description": "If set, the activity options will be restored to the default.\nDefault options are then options activity was created with.\nThey are part of the first SCHEDULE event.\nThis flag cannot be combined with any other option; if you supply\nrestore_original together with other options, the request will be rejected."
         }
       }
     },

openapi/openapiv3.yaml

@@ -11759,6 +11759,8 @@ components:
             If set, the activity options will be restored to the default.
              Default options are then options activity was created with.
              They are part of the first SCHEDULE event.
+             This flag cannot be combined with any other option; if you supply
+             restore_original together with other options, the request will be rejected.
     UpdateActivityOptionsResponse:
       type: object
       properties:

temporal/api/workflowservice/v1/request_response.proto

@@ -1846,6 +1846,8 @@ message UpdateActivityOptionsRequest {
     // If set, the activity options will be restored to the default.
     // Default options are then options activity was created with.
     // They are part of the first SCHEDULE event.
+    // This flag cannot be combined with any other option; if you supply
+    // restore_original together with other options, the request will be rejected.
     bool restore_original = 8;
 }