chore(deps): update dependency chai to v6

Author: renovate[bot]

package.json

@@ -31,7 +31,7 @@
     "semantic-release": "semantic-release"
   },
   "devDependencies": {
-    "chai": "4.3.4",
+    "chai": "6.2.1",
     "coffee-script": "1.12.7",
     "eslint": "6.8.0",
     "istanbul": "0.4.5",