Update dependency chai to v6

Author: renovate[bot]

package.json

@@ -41,7 +41,7 @@
     "babelify": "10.0.0",
     "body-parser": "2.2.0",
     "browserify": "17.0.1",
-    "chai": "4.5.0",
+    "chai": "6.0.1",
     "chai-as-promised": "7.1.2",
     "cssnano": "7.1.1",
     "del": "8.0.0",