Addition of the hostPID property to TestWorkflowSpec

[FraNemo]

Is your feature request related to a problem? Please describe.

I'm trying to perform a security analysis with kube-bench on my minikube cluster (k8s 1.28) through a TestWorkflow. As requested from the tool documentation (under "Running in a Kubernetes cluster" https://aquasecurity.github.io/kube-bench/v0.6.15/running/), when kube-bench is run inside a pod it requires the access to the host's PID namespace in order to completely execute the scan. This is allowed by the property "hostPID" set to "true" in the Job manifest. This field is not available in a TestWorkflow right now.

Describe the solution you'd like

Addition of the "hostPID" field to TestWorkflowSpec in order to allow this type of security test.

[vsukhin]

thank you @FraNemo cc @olensmar @jmorante-ks