Add test for using helm setFiles

[MarlonGamez]

This PR only adds a simple test to check that using setFiles in the helm deployer stanza adds the proper flag when running helm commands

[codecov]

Codecov Report

Merging #4735 into master will decrease coverage by 0.05%.
The diff coverage is 45.54%.

@@            Coverage Diff             @@
##           master    #4735      +/-   ##
==========================================
- Coverage   73.39%   73.34%   -0.06%     
==========================================
  Files         344      345       +1     
  Lines       13669    13708      +39     
==========================================
+ Hits        10033    10054      +21     
- Misses       3002     3021      +19     
+ Partials      634      633       -1     

Impacted Files	Coverage Δ
pkg/diag/validator/pod.go	1.60% <0.00%> (-0.08%)	⬇️
pkg/skaffold/runner/runner.go	0.00% <ø> (ø)
pkg/skaffold/deploy/status_check.go	52.25% <25.53%> (-6.81%)	⬇️
pkg/skaffold/runner/deploy.go	44.77% <50.00%> (ø)
pkg/skaffold/deploy/resource/logfile.go	84.61% <84.61%> (ø)
pkg/skaffold/deploy/resource/deployment.go	91.54% <88.00%> (+1.54%)	⬆️
pkg/skaffold/deploy/helm.go	79.03% <0.00%> (+0.80%)	⬆️
pkg/diag/validator/resource.go	58.82% <0.00%> (+5.88%)	⬆️

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[MarlonGamez]

Codecov seems to be behaving oddly on this PR. @tejal29 pointed out that it has the same diffs as a PR that she merged earlier #4690