docs: Add link to kustomization example for installing argocd

[rodrigc]

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[rodrigc]

This was mentioned in Slack here: https://cloud-native.slack.com/archives/C01TSERG0KZ/p1681768428770609?thread_ts=1681767293.487289&cid=C01TSERG0KZ

[codecov]

Codecov Report

Patch and project coverage have no change.

Comparison is base (ceed653) 49.01% compared to head (cdae1c3) 49.01%.

Additional details and impacted files

@@           Coverage Diff           @@
##           master   #13268   +/-   ##
=======================================
  Coverage   49.01%   49.01%           
=======================================
  Files         247      247           
  Lines       42685    42685           
=======================================
  Hits        20924    20924           
  Misses      19645    19645           
  Partials     2116     2116           

see 1 file with indirect coverage changes

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