chore: add argocd binary to argocd-test-tool docker image (#9459)

[cippaciong]

Fixes #9459

Checklist:

• Either (a) I've created an enhancement proposal and discussed it with the community, (b) this is a bug fix, or (c) this does not need to be in the release notes.
• The title of the PR states what changed and the related issues number (used for the release note).
• I've included "Closes [ISSUE #]" or "Fixes [ISSUE #]" in the description to automatically close the associated issue.
• I've updated both the CLI and UI to expose my feature, or I plan to submit a second PR with them.
• Does this PR require documentation updates?
• I've updated documentation as required by this PR.
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[codecov]

Codecov Report

Merging #9467 (2285066) into master (ba7d2e7) will not change coverage.
The diff coverage is n/a.

@@           Coverage Diff           @@
##           master    #9467   +/-   ##
=======================================
  Coverage   45.71%   45.71%           
=======================================
  Files         221      221           
  Lines       26289    26289           
=======================================
  Hits        12019    12019           
  Misses      12610    12610           
  Partials     1660     1660           

Impacted Files	Coverage Δ
util/settings/settings.go	48.16% <0.00%> (ø)

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[jannfis]

Please see my comment in #9459

[jannfis]

LGTM, thank you!