chore(deps-dev): bump vitest in /private/aws-protocoltests-restxml

Bumps [vitest](https://github.com/vitest-dev/vitest/tree/HEAD/packages/vitest) from 2.1.8 to 2.1.9.
- [Release notes](https://github.com/vitest-dev/vitest/releases)
- [Commits](https://github.com/vitest-dev/vitest/commits/v2.1.9/packages/vitest)

---
updated-dependencies:
- dependency-name: vitest
  dependency-version: 2.1.9
  dependency-type: direct:development
...

Signed-off-by: dependabot[bot] <[email protected]>

Author: dependabot[bot]

private/aws-protocoltests-restxml/package.json

@@ -70,7 +70,7 @@
     "downlevel-dts": "0.10.1",
     "rimraf": "3.0.2",
     "typescript": "~5.8.3",
-    "vitest": "2.1.8"
+    "vitest": "2.1.9"
   },
   "engines": {
     "node": ">=18.0.0"