Update dependency chai to v6

Author: renovate[bot]

package.json

@@ -44,7 +44,7 @@
     "@types/ultra-strftime": "^1.0.3",
     "@typescript-eslint/parser": "^7.14.1",
     "c8": "^10.1.2",
-    "chai": "^5.1.1",
+    "chai": "^6.0.1",
     "coveralls": "^3.1.1",
     "eslint": "^8.57.0",
     "eslint-config-prettier": "^9.1.0",