Build: Remove now-unused sample config relating to purging

Follows-up 57f9528.

Author: Krinkle

config-sample.json

@@ -2,12 +2,5 @@
 	"url": "vagrant.codeorigin.jquery.com",
 	"username": "admin",
 	"password": "secret",
-	"cdn_origin": "https://code.jquery.com",
-
-	"highwinds": {
-		"api_url": "https://striketracker.highwinds.com",
-		"api_token": "example_token",
-		"account_hash": "example_hash",
-		"file_hostname": "code.jquery.com"
-	}
+	"cdn_origin": "https://code.jquery.com"
 }