add case for suspend or shutdown vm via libvirt-guest service

[nanli1]

xxxx-300726:suspend or shutdown VM with PERSISTENT_ONLY - via restarting libvirt-guests.service Signed-off-by: nanli [email protected]

Existed two bugs xxxx-56142 xxxx-56145

avocado run --vt-type libvirt --test-runner=runner --vt-machine-type q35 managedsave.libvirt_guests.positive_test..with_transient_vm
 (1/8) type_specific.io-github-autotest-libvirt.managedsave.libvirt_guests.positive_test.no_parallel_shutdown.suspend_on_shutdown.default_vol.none_on_boot.with_transient_vm.persistent_only_none: PASS (79.00 s)
 (2/8) type_specific.io-github-autotest-libvirt.managedsave.libvirt_guests.positive_test.no_parallel_shutdown.suspend_on_shutdown.default_vol.none_on_boot.with_transient_vm.persistent_only_true: PASS (98.31 s)
 (3/8) type_specific.io-github-autotest-libvirt.managedsave.libvirt_guests.positive_test.no_parallel_shutdown.suspend_on_shutdown.default_vol.none_on_boot.with_transient_vm.persistent_only_false: FAIL: guest:avocado-vt-vm2 should be suspend on shutdown (98.57 s)
 (4/8) type_specific.io-github-autotest-libvirt.managedsave.libvirt_guests.positive_test.no_parallel_shutdown.suspend_on_shutdown.default_vol.none_on_boot.with_transient_vm.persistent_only_default: PASS (97.73 s)
 (5/8) type_specific.io-github-autotest-libvirt.managedsave.libvirt_guests.positive_test.no_parallel_shutdown.shutdown_on_shutdown.none_on_boot.with_transient_vm.persistent_only_none: ERROR: libvirt-guests failed to restart. Please check logs. (104.38 s)
 (6/8) type_specific.io-github-autotest-libvirt.managedsave.libvirt_guests.positive_test.no_parallel_shutdown.shutdown_on_shutdown.none_on_boot.with_transient_vm.persistent_only_true: PASS (102.53 s)
 (7/8) type_specific.io-github-autotest-libvirt.managedsave.libvirt_guests.positive_test.no_parallel_shutdown.shutdown_on_shutdown.none_on_boot.with_transient_vm.persistent_only_false: ERROR: libvirt-guests failed to restart. Please check logs. (101.30 s)
 (8/8) type_specific.io-github-autotest-libvirt.managedsave.libvirt_guests.positive_test.no_parallel_shutdown.shutdown_on_shutdown.none_on_boot.with_transient_vm.persistent_only_default: ERROR: libvirt-guests failed to restart. Please check logs. (98.09 s)