chore(deps-dev): bump vitest from 4.0.14 to 4.0.15 (#383)

Bumps [vitest](https://github.com/vitest-dev/vitest/tree/HEAD/packages/vitest) from 4.0.14 to 4.0.15.
- [Release notes](https://github.com/vitest-dev/vitest/releases)
- [Commits](https://github.com/vitest-dev/vitest/commits/v4.0.15/packages/vitest)

---
updated-dependencies:
- dependency-name: vitest
  dependency-version: 4.0.15
  dependency-type: direct:development
  update-type: version-update:semver-patch
...

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Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>

Author: dependabot[bot]

packages/toolbar/package.json

@@ -103,7 +103,7 @@
     "storybook-addon-rslib": "^2.1.6",
     "storybook-react-rsbuild": "^2.1.6",
     "typescript": "^5.9.3",
-    "vitest": "^4.0.13"
+    "vitest": "^4.0.15"
   },
   "peerDependencies": {
     "launchdarkly-js-client-sdk": ">=3.9.0 <4.0.0",