Fix Wrk CPU affinity process invocation and ParametersOn condition evaluation

[RakeshwarK]

Issues fixed:

• The original approach wrapped the numactl command via bash -c "numactl ... "args"", but wrk arguments contain embedded double quotes (e.g., --header "Accept: application/json"), which broke the nested quoting.
• Override values from a ParametersOn section were merged into the evaluation context before the condition was evaluated, causing the condition itself to evaluate differently than intended.