Bump openresty to 1.21.4.3

[tkan145]

What

Upgrade openresty to 1.21.4.3. https://issues.redhat.com/browse/THREESCALE-10601

Verification steps

No code changes and all tests pass so I'll keep the verification steps simple:

• Create an apicast-config.json file with the following content

  cat <<EOF >apicast-config.json
  {
  "services": [
  {
    "backend_version": "1",
    "id": "1",
    "proxy": {
       "hosts": ["one"],
       "api_backend": "https://echo-api.3scale.net:443",
       "authentication_method":"2",
      "backend": {
        "endpoint": "http://127.0.0.1:8081",
        "host": "backend"
      },
      "policy_chain": [
        {
          "name": "apicast.policy.apicast"
        }
      ],
      "proxy_rules": [
        {
          "http_method": "GET",
          "pattern": "/",
          "metric_system_name": "hits",
          "delta": 1,
          "parameters": [],
          "querystring_parameters": {}
        }
      ]
    }
  }
  ]
  }
  EOF

• Checkout this branch and start dev environment

  make development
  make dependencies

• Verify the openresty version

  bash-4.4$ openresty -v

  It should output the following nginx version: openresty/1.21.4.3

• Run apicast locally

  THREESCALE_DEPLOYMENT_ENV=staging APICAST_LOG_LEVEL=warn APICAST_WORKER=1 APICAST_CONFIGURATION_LOADER=lazy APICAST_CONFIGURATION_CACHE=0 THREESCALE_CONFIG_FILE=apicast-config.json ./bin/apicast

• Capture apicast IP

  APICAST_IP=$(docker inspect apicast_build_0-development-1 | yq e -P '.[0].NetworkSettings.Networks.apicast_build_0_default.IPAddress' -)

• Send a request

  curl -i -k -H "Host: one" "http://${APICAST_IP}:8080/test?user_key="

  The response should be HTTP/1.1 200

  < HTTP/1.1 200 OK
  < Server: openresty
  < Date: Wed, 01 May 2024 02:44:05 GMT
  < Content-Type: application/json
  < Content-Length: 568
  < Connection: keep-alive
  < x-3scale-echo-api: echo-api/1.0.3
  < vary: Origin
  < x-content-type-options: nosniff
  < x-envoy-upstream-service-time: 1