Added tracking for deleted namespace status check in restore flow

[sangitaray2021]

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Does your change fix a particular issue?

Fixes #8234

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• Accepted the DCO. Commits without the DCO will delay acceptance.
• Created a changelog file (make new-changelog) or comment /kind changelog-not-required on this PR.
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[anshulahuja98]

For - #8234

[codecov]

Codecov Report

Attention: Patch coverage is 89.79592% with 5 lines in your changes missing coverage. Please review.

Project coverage is 58.98%. Comparing base (3f9c2dc) to head (6a5e8c2).
Report is 75 commits behind head on main.

Files with missing lines	Patch %	Lines
pkg/util/kube/resource_deletionstatus_tracker.go	76.19%	5 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #8233      +/-   ##
==========================================
- Coverage   59.15%   58.98%   -0.18%     
==========================================
  Files         367      368       +1     
  Lines       30777    38929    +8152     
==========================================
+ Hits        18206    22962    +4756     
- Misses      11113    14505    +3392     
- Partials     1458     1462       +4     

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[kaovilai]

Please add changelog and run linter.

[reasonerjt]

Given we've reached FC and this may impact the restore flow, let's hold this one until the branch is cut for v1.15

[anshulahuja98]

@kaovilai can you help review the PR?

[kaovilai]

IIUC from reviewing, this change reduce potential duplicate await on if namespace exists (wait for 10 min polling) to just one instance per restore. Is that correct?

It's not meant to add polling until deletion is complete to resume some other process?

[sangitaray2021]

IIUC from reviewing, this change reduce potential duplicate await on if namespace exists (wait for 10 min polling) to just one instance per restore. Is that correct?

It's not meant to add polling until deletion is complete to resume some other process?

yes thats correct. We are reducing duplicate wait by caching the namespace which is under deletion.

[kaovilai]

lgtm

[anshulahuja98]

@reasonerjt can you review this PR now given 1.15 is cut?