The test_wfs_france test is flaky and often fails

[greglucas]

Here is a recent log of a failure, but it shows up pretty regularly for timeouts, authorization errors. https://github.com/SciTools/cartopy/actions/runs/15201132029/job/42755356584#step:9:268

I'm wondering if there is a different way we can test this or store the response somehow for the CI/testing runs to make this more robust.

cc @mcuntz for any thoughts?