opinions.united_states_backscrapers folder excluded from tests

[grossir]

All scrapers in this folder are excluded from tests, notably test_ScraperExampleTest and test_ScraperExtractFromTextTest which may lead to errors when developing.

Also, federal_district and federal_appellate folders have HTML files per each scraper inside them, which does not follows the conventions in other parts of juriscraper of having the examples file in a different folder. This may lead to confusion to new developers / volunteers

[mlissner]

Definitely should fix the example files so they're consistent.

I'm not sure it's worth fixing the backscrapers though. The idea, historically, was always that they were one-off tools, and so if they worked the one time, then they were fine — no tests needed. But I could see how if we're doing more backscraping, having tests would make sense. What do you suggest?