Bump deepmerge from 4.2.2 to 4.3.0 (#6598)

Bumps [deepmerge](https://github.com/TehShrike/deepmerge) from 4.2.2 to 4.3.0.
- [Release notes](https://github.com/TehShrike/deepmerge/releases)
- [Changelog](https://github.com/TehShrike/deepmerge/blob/master/changelog.md)
- [Commits](TehShrike/deepmerge@v4.2.2...v4.3.0)

---
updated-dependencies:
- dependency-name: deepmerge
  dependency-type: direct:development
  update-type: version-update:semver-minor
...

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

package.json

@@ -173,7 +173,7 @@
     "@types/write-file-atomic": "^4.0.0",
     "benchmark": "^2.1.4",
     "common-tags": "^1.8.2",
-    "deepmerge": "^4.2.2",
+    "deepmerge": "^4.3.0",
     "eslint": "^8.33.0",
     "eslint-config-stylelint": "^17.1.0",
     "husky": "^8.0.3",