Bump @types/js-yaml from 4.0.5 to 4.0.9 in /generator

Bumps [@types/js-yaml](https://github.com/DefinitelyTyped/DefinitelyTyped/tree/HEAD/types/js-yaml) from 4.0.5 to 4.0.9.
- [Release notes](https://github.com/DefinitelyTyped/DefinitelyTyped/releases)
- [Commits](https://github.com/DefinitelyTyped/DefinitelyTyped/commits/HEAD/types/js-yaml)

---
updated-dependencies:
- dependency-name: "@types/js-yaml"
  dependency-type: direct:development
  update-type: version-update:semver-patch
...

Signed-off-by: dependabot[bot] <support@github.com>

generator/package.json

@@ -23,7 +23,7 @@
     "@autorest/core": "^3.9.7",
     "@ts-common/commonmark-to-markdown": "^2.0.2",
     "@types/async": "^3.2.20",
-    "@types/js-yaml": "^4.0.5",
+    "@types/js-yaml": "^4.0.9",
     "@types/lodash": "^4.14.200",
     "@types/node": "^20.4.4",
     "@types/yargs": "^17.0.24",