This was determined programmatically by means of trying to do a simple
HTTP request to / of any of the URLs given:
```python
from lxml import etree
from urllib import parse
import requests
doc = etree.parse("ultimate_providers.xml")
root = doc.getroot()
for provider in root:
parsed_url = parse.urlparse(provider.get("url"))
url = f"{parsed_url.scheme}://{parsed_url.netloc}/"
try:
requests.head(url, timeout=5)
except Exception as e:
print(parsed_url.netloc)
```
Note that these were also removed from songinfoview as present, and from
outgoingdatacreator. The two lists there were found to be inconsistent,
but this isn't subject of this PR.
Signed-off-by: Marcus Müller <marcus_clementine@baseband.digital>