Fix multiple errors and warnings in kube-burner output across cnv-scenarios:

• Replace deprecated spec.running with spec.runStrategy in all VM templates and check scripts
• Make jq expression null-safe in virt-capacity-benchmark to avoid errors on empty conditions
• Scope vmiLatency/pvcLatency measurements to the create-vms job and add proper waitOptions for DataVolumes in per-host-density

PR: https://github.com/guchen11/cnv-scenarios/pull/new/fix-output-errors-warnings
GitHub Issue: https://github.com/redhat-vmeperf/cnv-scenarios/issues/3

Tested on lab cluster (cpu-limits --mode sanity) — all scenarios pass.