build(deps-dev): bump @ember/test-helpers from 2.9.3 to 2.9.4

Bumps [@ember/test-helpers](https://github.com/emberjs/ember-test-helpers) from 2.9.3 to 2.9.4.
- [Release notes](https://github.com/emberjs/ember-test-helpers/releases)
- [Changelog](https://github.com/emberjs/ember-test-helpers/blob/v2.9.4/CHANGELOG.md)
- [Commits](emberjs/ember-test-helpers@v2.9.3...v2.9.4)

---
updated-dependencies:
- dependency-name: "@ember/test-helpers"
  dependency-type: direct:development
  update-type: version-update:semver-patch
...

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

yarn.lock

@@ -1030,9 +1030,9 @@
     ember-cli-babel "^7.26.6"
 
 "@ember/test-helpers@^2.9.3":
-  version "2.9.3"
-  resolved "https://registry.yarnpkg.com/@ember/test-helpers/-/test-helpers-2.9.3.tgz#c2a9d6ab1c367af92cf1a334f97eb19b8e06e6e1"
-  integrity sha512-ejVg4Dj+G/6zyLvQsYOvmGiOLU6AS94tY4ClaO1E2oVvjjtVJIRmVLFN61I+DuyBg9hS3cFoPjQRTZB9MRIbxQ==
+  version "2.9.4"
+  resolved "https://registry.yarnpkg.com/@ember/test-helpers/-/test-helpers-2.9.4.tgz#985022e9ba05cfc918bcf08b77cbb355f85b723e"
+  integrity sha512-z+Qs1NYWyIVDmrY6WdmOS5mdG1lJ5CFfzh6dRhLfs9lq45deDaDrVNcaCYhnNeJZTvUBK2XR2SvPcZm0RloXdA==
   dependencies:
     "@ember/test-waiters" "^3.0.0"
     "@embroider/macros" "^1.10.0"