Test framework for evaluating if a backup integration works properly

[ShellyKa13]

What this PR does / why we need it: The PR improved tests framework by handling namespace creation and deletion in the general test framework instead in each test context. Handle clients creation better. Create yaml that can be used also for other backup/restore providers to test if their tools integrates properly with kubevirt. Adjust test to consume this yaml to make sure the yamls will not go old an outdated without notice. Add some more test for backup and restore.

Which issue(s) this PR fixes (optional, in fixes #<issue number>(, fixes #<issue_number>, ...) format, will close the issue(s) when PR gets merged): Fixes #

Special notes for your reviewer:

Release note:

Add yamls to be used to make sure backup integration works properly

[ShellyKa13]

@mhenriks Thanks! I checked and there are several standalone VMI tests which I can convert to also consume yamls and create appropriate yamls. Regarding VMIRS I understand its missing need to also add relevant backup/restore action items so it will be done in different PR. Same for GC, I am working on adjusting all the tests to work both with and without GC. will be on different PR.

[ShellyKa13]

fixed @akalenyu comments. Converted the positive standalone VMI test to consume yaml like @mhenriks asked. GC and VMIRS will be in different PRs.

[mhenriks]

Great work @ShellyKa13!

/lgtm /approve

[kubevirt-bot]

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