Add dependencies for testing

Author: jcreedcmu

common/config/rush/pnpm-lock.yaml

@@ -444,6 +444,8 @@
     "webpack-cli": "^3.3.2",
     "eslint": "~6.8.0",
     "@typescript-eslint/eslint-plugin": "~2.23.0",
-    "@typescript-eslint/parser": "~2.23.0"
+    "@typescript-eslint/parser": "~2.23.0",
+    "chai-as-promised": "~7.1.1",
+    "@types/chai-as-promised": "~7.1.2"
   }
 }