Added caching for namespace status check in restore path

[sangitaray2021]

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[codecov]

Codecov Report

Attention: Patch coverage is 72.97297% with 10 lines in your changes missing coverage. Please review.

Project coverage is 59.15%. Comparing base (3f9c2dc) to head (6112573).
Report is 4 commits behind head on main.

Files with missing lines	Patch %	Lines
pkg/util/kube/utils.go	72.97%	5 Missing and 5 partials ⚠️

Additional details and impacted files

@@           Coverage Diff           @@
##             main    #8219   +/-   ##
=======================================
  Coverage   59.15%   59.15%           
=======================================
  Files         367      367           
  Lines       30777    30789   +12     
=======================================
+ Hits        18206    18214    +8     
- Misses      11113    11115    +2     
- Partials     1458     1460    +2     

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