Fix chai ambient type error

Author: DanielCliftonGuardian

dotcom-rendering/package.json

@@ -67,6 +67,7 @@
 		"@testing-library/react": "16.3.0",
 		"@testing-library/user-event": "14.6.1",
 		"@types/body-parser": "1.19.2",
+		"@types/chai": "5.2.2",
 		"@types/clean-css": "4.2.11",
 		"@types/compression": "1.7.5",
 		"@types/connect": "3.4.38",