PTFM-17914 Fix test_download_url_helper on Windows
PTFM-17914 Fix test_download_url_helper on Windows

Summary:

test_dxpy.TestDXFile.test_download_url_helper fails on Windows unless we pass a 30s duration to dxfile.get_download_url() in one of the second batch of download URLs the test generates.

Test Plan:

Tested fix in Powershell with:

python .\build\run_python_integration_tests.py --tests `
    test_dxpy.TestDXFile.test_download_url_helper
dnanexus/dx-toolkit,dnanexus/dx-toolkit,jhuttner/dx-toolkit,dnanexus/dx-toolkit,jhuttner/dx-toolkit,dnanexus/dx-toolkit,dnanexus/dx-toolkit,dnanexus/dx-toolkit,jhuttner/dx-toolkit,dnanexus/dx-toolkit,jhuttner/dx-toolkit,jhuttner/dx-toolkit,jhuttner/dx-toolkit,dnanexus/dx-toolkit,jhuttner/dx-toolkit,jhuttner/dx-toolkit