Support kubevirt tests on sle-micro 6.0

[nanzhg]

1. Add slem-kubevirt-tests.yaml
2. Add live migration into core tests
3. Enable NTP service
4. Setup cnv-bridge containernetworking plugin
5. Set the value of default storage class with true
6. Optimize Whereabouts plugin downloading

• Related ticket: https://progress.opensuse.org/issues/138638
• Verification run:
  sle-micro 6.0 - http://10.67.129.96/tests/3186
  sles15 sp6 - http://10.67.129.96/tests/3191

[alice-suse]

Thanks for the great PR! I left only some minor comments inline.

But I may leave here a major comment:
in the html report http://10.67.129.96/tests/3173/file/all-tests.html, it is sooooo hard to find the short list that are really executed, no matter pass or fail. Besides, the uploaded log files, eg vnc_test.log, it's not very well readable. Would you please give it a high priority to enhance the report and logs from those regards? Not necessarily in this PR, but better with a following PR soon.

[nanzhg]

Thanks for the great PR! I left only some minor comments inline.

But I may leave here a major comment: in the html report http://10.67.129.96/tests/3173/file/all-tests.html, it is sooooo hard to find the short list that are really executed, no matter pass or fail. Besides, the uploaded log files, eg vnc_test.log, it's not very well readable. Would you please give it a high priority to enhance the report and logs from those regards? Not necessarily in this PR, but better with a following PR soon.

You can use command "iconv vnc_test.log" to output the original log. Anyway, will enhance the report in future PR. Thanks

[alice-suse]

LGTM