Bump deepmerge from 3.3.0 to 4.2.2

Bumps [deepmerge](https://github.com/TehShrike/deepmerge) from 3.3.0 to 4.2.2.
- [Release notes](https://github.com/TehShrike/deepmerge/releases)
- [Changelog](https://github.com/TehShrike/deepmerge/blob/master/changelog.md)
- [Commits](TehShrike/deepmerge@v3.3.0...v4.2.2)

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

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

package.json

@@ -51,7 +51,7 @@
     "chai": "^4.2.0",
     "colors": "^1.4.0",
     "cross-env": "^7.0.3",
-    "deepmerge": "^3.3.0",
+    "deepmerge": "^4.2.2",
     "microbundle": "^0.13.0",
     "mocha": "^8.2.1",
     "rollup": "^1.32.1",