make test-e2e fails on `yaml` module not found

[moficodes]

make test-e2e at some point calls https://github.com/kubernetes-sigs/agent-sandbox/blob/main/dev/tools/deploy-to-kube which tries to import yaml. This package is not part of python std lib.

the test fails with

Traceback (most recent call last):
  File "/home/user/github.com/kubernetes-sigs/agent-sandbox/dev/tools/deploy-to-kube", line 20, in <module>
    import yaml
ModuleNotFoundError: No module named 'yaml'