Upgrade sinon-chai to v4

Required for chai v6 compatibility

Author: Ndpnt

package-lock.json

@@ -116,7 +116,7 @@
     "prettier": "^2.2.1",
     "semver": "^7.6.0",
     "sinon": "^12.0.1",
-    "sinon-chai": "^3.7.0",
+    "sinon-chai": "^4.0.1",
     "supertest": "^6.3.3"
   },
   "peerDependencies": {