[ci] fix s5cmd path in chainsaw test for kubeadm-full

[AshleyDumaine]

What this PR does / why we need it: s5cmd is now in GOPATH/bin/ (which should be automatically in the PATH) since the tool is now installed via go tool.

Which issue(s) this PR fixes (optional, in fixes #<issue number>(, fixes #<issue_number>, ...) format, will close the issue(s) when PR gets merged):
Fixes #

Special notes for your reviewer:

TODOs:

• squashed commits
• includes documentation
• adds unit tests
• adds or updates e2e tests

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 65.94%. Comparing base (955307b) to head (754e61d).
⚠️ Report is 1 commits behind head on main.

Additional details and impacted files

@@           Coverage Diff           @@
##             main     #905   +/-   ##
=======================================
  Coverage   65.94%   65.94%           
=======================================
  Files          71       71           
  Lines        7958     7958           
=======================================
  Hits         5248     5248           
  Misses       2408     2408           
  Partials      302      302           

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