karmada-search install by helm support specify external etcd

[my-git9]

What type of PR is this?
/kind feature

What this PR does / why we need it:

Which issue(s) this PR fixes:
Fixes #3119

Special notes for your reviewer:

Does this PR introduce a user-facing change?:

Chart: karmada-search install support specify external etcd

[codecov-commenter]

Codecov Report

Merging #3120 (0150b5b) into master (8a69413) will not change coverage.
The diff coverage is n/a.

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@@           Coverage Diff           @@
##           master    #3120   +/-   ##
=======================================
  Coverage   44.48%   44.48%           
=======================================
  Files         208      208           
  Lines       19524    19524           
=======================================
  Hits         8686     8686           
  Misses      10357    10357           
  Partials      481      481           

Flag	Coverage Δ
unittests	44.48% <ø> (ø)

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[Poor12]

/lgtm
/approve

[karmada-bot]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: Poor12

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• charts/OWNERS [Poor12]

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