Mark tests that use the network

[QuLogic]

These two tests uses intersphinx, and the marker allows skipping them if there is no network available.

[AWhetter]

Thanks for making this change. Why is this needed?

[QuLogic]

This is useful for downstream packaging; in such cases builds aren't allowed to access the Internet at large, and instead of skipping all tests, it is useful to skip only the ones that require networking. I don't know that network is a standard name anywhere, but at least it's the one I suggest when making PRs like this.

[cclauss]

To get the GitHub Actions to pass...

echo "Mark pytests that use the network" > docs/changes/462.misc.rst
git add docs/changes/462.misc.rst
git commit -m"git add docs/changes/462.misc.rst"
git push

[QuLogic]

Thanks for the ping; I've fixed that, and the conflict.

[AWhetter]

Thanks for fixing this yourself and keep the pull request up to date. I've merged this as 0d5f21b