iago-test image: "toomanyrequests: You have reached your pull rate limit. (docker hub?)

[meling]

Tests are failing on #171.

{"errorDetail":{"message":"toomanyrequests: You have reached your pull rate limit. You may increase the limit by authenticating and upgrading: https://www.docker.com/increase-rate-limit"},"error":"toomanyrequests: You have reached your pull rate limit. You may increase the limit by authenticating and upgrading: https://www.docker.com/increase-rate-limit"}
    iagotest.go:171: Error response from daemon: No such image: iago-test:latest
--- FAIL: TestDeployment (1.45s)
FAIL
FAIL	github.com/relab/hotstuff/internal/orchestration	84.933s