Niconico seriesIE no longer working after url update

[sqrtNOT]

Basically the url format for series pages on niconico changed from just pointing at the series to including the user information in the url. Example:
https://www.nicovideo.jp/series/110226 now redirects to https://www.nicovideo.jp/user/44113208/series/110226
Old urls are still valid through the redirect but the previous extractor's way of extracting the videos is not so that was updated as well.
Also in lieu of adding a specific test for this new url format I just edited one of the old format ones since we had multiple.

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