wbclive API tests

• Health /healthz
• Static JSON /static.json
• Dynamic JSON /dynamic.json
• PNG (32,974 bytes) /images/32k.png
• PNG (262,799 bytes) /images/256k.png
• PNG (1,049,983 bytes) /images/1m.png
• PNG (4,197,695 bytes) /images/4m.png
• Plain text payload /payload/plain
• Same payload, gzip /payload/gzip
• HTTP 204 /status/204
• HTTP 400 /status/400
• HTTP 404 /status/404
• HTTP 429 /status/429
• HTTP 500 /status/500
• HTTP 503 /status/503