fix flake TestGetSetFileValues

[tejal29]

Fixes #2935

Description

Sort the array before checking.

 go test github.com/GoogleContainerTools/skaffold/pkg/skaffold/deploy -run TestGetSetFileValues --count=100
ok  	github.com/GoogleContainerTools/skaffold/pkg/skaffold/deploy	0.213s

User facing changes

n/a

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• The code flow looks good.
• Unit test added.
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Release Notes

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[codecov]

Codecov Report

Merging #2936 into master will not change coverage.
The diff coverage is n/a.