[cherry-pick][release-1.12]Fix #6752: add namespace exclude check.

[blackpiglet]

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[codecov]

Codecov Report

Merging #6762 (5303964) into release-1.12 (1b2c82c) will increase coverage by 0.03%.
The diff coverage is 100.00%.

❗ Current head 5303964 differs from pull request most recent head 4d16174. Consider uploading reports for the commit 4d16174 to get more accurate results

@@               Coverage Diff                @@
##           release-1.12    #6762      +/-   ##
================================================
+ Coverage         60.43%   60.46%   +0.03%     
================================================
  Files               242      242              
  Lines             26017    26007      -10     
================================================
+ Hits              15723    15726       +3     
+ Misses             9191     9180      -11     
+ Partials           1103     1101       -2     

Files Changed	Coverage Δ
pkg/backup/item_collector.go	58.11% <100.00%> (-0.24%)	⬇️
pkg/install/resources.go	78.13% <100.00%> (+0.35%)	⬆️

... and 1 file with indirect coverage changes