Update kubectl-plugin docs

[aledbf]

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[aledbf]

/retest

[codecov-io]

Codecov Report

Merging #4582 into master will decrease coverage by 0.01%.
The diff coverage is n/a.

@@            Coverage Diff            @@
##           master   #4582      +/-   ##
=========================================
- Coverage   58.61%   58.6%   -0.02%     
=========================================
  Files          88      88              
  Lines        6701    6701              
=========================================
- Hits         3928    3927       -1     
+ Misses       2340    2339       -1     
- Partials      433     435       +2

Impacted Files	Coverage Δ
internal/ingress/metric/collectors/process.go	88.29% <0%> (-2.13%)	⬇️
internal/watch/file_watcher.go	84.61% <0%> (+3.84%)	⬆️

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