docs: update readChanges startTime docs to reflect inclusion in body (#…

…485)

config/clients/go/template/README_calling_api.mustache

@@ -205,13 +205,13 @@ Reads the list of historical relationship tuple writes and deletes.
 ```golang
 body := ClientReadChangesRequest{
     Type: "document",
+    StartTime: {{packageName}}.PtrString("2022-01-01T00:00:00Z"),
 }
 options := ClientReadChangesOptions{
     PageSize: {{packageName}}.PtrInt32(10),
     ContinuationToken: {{packageName}}.PtrString("eyJwayI6IkxBVEVTVF9OU0NPTkZJR19hdXRoMHN0b3JlIiwic2siOiIxem1qbXF3MWZLZExTcUoyN01MdTdqTjh0cWgifQ=="),
     // You can rely on the store id set in the configuration or override it for this specific request
     StoreId: {{packageName}}.PtrString("01FQH7V8BEG3GPQW93KTRFR8JB"), 
-    StartTime: {{packageName}}.PtrString("2022-01-01T00:00:00Z"),
 }
 data, err := fgaClient.ReadChanges(context.Background()).Body(body).Options(options).Execute()