chore(deps-dev): bump @babel/plugin-proposal-decorators

Bumps [@babel/plugin-proposal-decorators](https://github.com/babel/babel/tree/HEAD/packages/babel-plugin-proposal-decorators) from 7.23.6 to 7.23.9.
- [Release notes](https://github.com/babel/babel/releases)
- [Changelog](https://github.com/babel/babel/blob/main/CHANGELOG.md)
- [Commits](https://github.com/babel/babel/commits/v7.23.9/packages/babel-plugin-proposal-decorators)

---
updated-dependencies:
- dependency-name: "@babel/plugin-proposal-decorators"
  dependency-type: direct:development
  update-type: version-update:semver-patch
...

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

package.json

@@ -65,7 +65,7 @@
     "@adfinis/eslint-config": "2.1.0",
     "@adfinis/semantic-release-config": "4.1.0",
     "@babel/eslint-parser": "7.23.3",
-    "@babel/plugin-proposal-decorators": "7.23.6",
+    "@babel/plugin-proposal-decorators": "7.23.9",
     "@ember/optional-features": "2.0.0",
     "@ember/test-helpers": "3.2.1",
     "@embroider/test-setup": "3.0.3",