fix(tests): mark test_download_and_unzip flaky (#11)

Author: wpbonelli

modflow_devtools/test/test_download.py

@@ -1,8 +1,10 @@
 import pytest
+from flaky import flaky
 from modflow_devtools.download import download_and_unzip
 from modflow_devtools.markers import requires_github
 
 
+@flaky
 @requires_github
 @pytest.mark.parametrize("delete_zip", [True, False])
 def test_download_and_unzip(function_tmpdir, delete_zip):