chore(deps): update dependency @testing-library/dom to v9.3.0

Author: renovate[bot]

package-lock.json

@@ -38,7 +38,7 @@
     "@edx/frontend-build": "12.8.27",
     "@edx/frontend-platform": "4.2.0",
     "@edx/reactifex": "^2.1.1",
-    "@testing-library/dom": "9.2.0",
+    "@testing-library/dom": "9.3.0",
     "@testing-library/jest-dom": "5.16.5",
     "@testing-library/react": "10.4.9",
     "enzyme": "3.11.0",