Add example to the user guide: how to determine who create or last modified a resource

[FedericoNegri]

Example code snippet for jobs (same works for task and job definitions):

from ansys.hps.client import Client, ProjectApi, AuthApi

cl = Client(username="repuser", password="repuser")

project_api = ProjectApi(cl, "02vm5JzrGmkhOX87It1Cnd")
auth_api = AuthApi(cl)

# job
job = project_api.get_jobs()[0]

created_by = auth_api.get_user(id=job.created_by)
modified_by = auth_api.get_user(id=job.modified_by)

print(
    f"Job '{job.name}' was created by '{created_by.username}' "
    f"and last modified by '{modified_by.username}'"
)