flash/update で部分的に変更できるようにする (#13396)

* make flash/update params optional

* Update autogen files

pnpm run build-misskey-js-with-types

* Update update.ts

* Update CHANGELOG.md

* hasOwnProperty -> hasOwn

Co-authored-by: syuilo <4439005+syuilo@users.noreply.github.com>

---------

Co-authored-by: syuilo <4439005+syuilo@users.noreply.github.com>

packages/misskey-js/src/autogen/types.ts

@@ -22927,10 +22927,10 @@ export type operations = {
         'application/json': {
           /** Format: misskey:id */
           flashId: string;
-          title: string;
-          summary: string;
-          script: string;
-          permissions: string[];
+          title?: string;
+          summary?: string;
+          script?: string;
+          permissions?: string[];
           /** @enum {string} */
           visibility?: 'public' | 'private';
         };