Make subdirs in tests/io/data

[alimcmaster1]

• closes TST: make subdirs in pandas/tests/io/data #29439
• passes black pandas
• passes git diff upstream/master -u -- "*.py" | flake8 --diff

A few of the "network" tests are failing locally as they require the data on master:
e.g

  @tm.network
    def test_spam_url(self):
        url = (
            "https://raw.githubusercontent.com/pandas-dev/pandas/master/"
            "pandas/tests/io/data/html/spam.html"
        )
        df1 = self.read_html(url, ".*Water.*")
        df2 = self.read_html(url, "Unit")

        assert_framelist_equal(df1, df2)

^ Will change to this branch to get the test passing on this PR. Then in a follow up PR will revert to master unless any core devs have a different idea

[pep8speaks]

Hello @alimcmaster1! Thanks for updating this PR. We checked the lines you've touched for PEP 8 issues, and found:

There are currently no PEP 8 issues detected in this Pull Request. Cheers! 🍻

Comment last updated at 2019-11-13 14:52:13 UTC

[WillAyd]

Yea the network stuff is a little wonky to manage when doing this, but note there is also non-network stuff mixed in. Out of the azure stuff I think only py36_locale_slow_old_np actually runs the network tests, so rest should be green

[alimcmaster1]

Test failures now just 1 test related to - #29514

[jreback]

i think if you merge master this will be green.

[jreback]

thanks !

[alimcmaster1]

No worries - I’ll attempt to fix that flakey test mentioned above