[BE Feat] Implement base test setup

[juancwu]

Description

Implement helper setup functions for a minimal test environment.

Example usage:

func TestMain(m *testing.M) {
  setup()
  code := m.Run()
  cleanup()
  os.Exit(code)
}

Checklist

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• Is labelled properly - if this is a refactor, add the label!
• Has the SPUR project assigned to it.
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