Update dependency @firebase/rules-unit-testing to v5

Author: renovate[bot]

package.json

@@ -527,7 +527,7 @@
     "@eslint/compat": "1.3.2",
     "@eslint/eslintrc": "3.3.1",
     "@eslint/js": "9.32.0",
-    "@firebase/rules-unit-testing": "4.0.1",
+    "@firebase/rules-unit-testing": "5.0.0",
     "@rollup/plugin-commonjs": "28.0.6",
     "@rollup/plugin-node-resolve": "16.0.1",
     "@stylistic/eslint-plugin": "5.2.3",