retry deleting test ns after reconnecting cloud node

[Congrool]

What type of PR is this?

/kind bug

What this PR does / why we need it:

After execution of docker reconnect to reconnect the cloud node, there may have a little before the cloud node can be actually visited. So, we'd better keep retry when deleting namespace.

Which issue(s) this PR fixes:

Fixes #1054

Special notes for your reviewer:

Does this PR introduce a user-facing change?

other Note

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In response to this:

What type of PR is this?

/kind bug

What this PR does / why we need it:

After execution of docker reconnect to reconnect the cloud node, there may have a little before the cloud node can be actually visited. So, we'd better keep retry when deleting namespace.

Which issue(s) this PR fixes:

Fixes #1054

Special notes for your reviewer:

Does this PR introduce a user-facing change?

other Note

Instructions for interacting with me using PR comments are available here. If you have questions or suggestions related to my behavior, please file an issue against the kubernetes/test-infra repository.

[codecov]

Codecov Report

Merging #1060 (87e8877) into master (45266e0) will not change coverage.
The diff coverage is n/a.

@@           Coverage Diff           @@
##           master    #1060   +/-   ##
=======================================
  Coverage   49.47%   49.47%           
=======================================
  Files          96       96           
  Lines       13056    13056           
=======================================
  Hits         6460     6460           
  Misses       6060     6060           
  Partials      536      536           

Flag	Coverage Δ
unittests	49.47% <ø> (ø)

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[Congrool]

I think it's fixed, PTAL @rambohe-ch

We can rerun it several times to ensure it.

[rambohe-ch]

/lgtm
/approve

[openyurt-bot]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: Congrool, rambohe-ch

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• OWNERS [rambohe-ch]

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