Update developer dependencies

Since we are only updating developer dependencies, we can gain enough
confidence in this change by making sure the test task exists cleanly.

package.json

@@ -29,14 +29,14 @@
   "devDependencies": {
     "@github/prettier-config": "0.0.4",
     "chai": "^4.3.4",
-    "eslint": "^7.27.0",
-    "eslint-plugin-github": "^4.1.3",
+    "eslint": "^8.6.0",
+    "eslint-plugin-github": "^4.3.5",
     "karma": "^6.3.2",
     "karma-chai": "^0.1.0",
     "karma-chrome-launcher": "^3.1.0",
     "karma-mocha": "^2.0.1",
-    "karma-mocha-reporter": "^2.2.5",
-    "mocha": "^8.4.0",
+    "karma-mocha-reporter": "^2.2.3",
+    "mocha": "^9.1.3",
     "typescript": "^4.2.4"
   },
   "eslintIgnore": [