chore(deps): update dependency chai to v6

Author: renovate[bot]

package.json

@@ -20,7 +20,7 @@
   "devDependencies": {
     "@pact-foundation/pact": "16.3.0",
     "@pact-foundation/pact-cli": "18.0.0",
-    "chai": "^4.3.10",
+    "chai": "^6.0.0",
     "chai-as-promised": "^7.1.1",
     "cross-env": "10.1.0",
     "mocha": "11.7.5",