[ceskatelevize] Update to 2021-12-06 changes (#1899)

[mkubecek]

After a site redesign on 2021-12-06, player iframe is no longer present in
the page from the start and is only inserted after pressing the "play"
button. We need to query /v-api/iframe-hash/ to get hash to pass to
iFramePlayer.php and extract "IDEC" id from a json in the original page.

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Fix downloading from www.ceskatelevize.cz after website redesign of 2012-06-12.

[dirkf]

With 2021-12-20 master, extractor test 0 fails (RegexNotFoundError: [CeskaTelevize] 20641-bonus-01-en: Unable to extract type) and the metadata extraction fails in test 2 (Invalid value for field title, expected 'Queer: Bogotart', got 'Bogotart - Queer | Česká televize').

There has been another commit after this PR but it shouldn't have caused those failures.

[mkubecek]

With 2021-12-20 master, extractor test 0 fails (RegexNotFoundError: [CeskaTelevize] 20641-bonus-01-en: Unable to extract type) and the metadata extraction fails in test 2 (Invalid value for field title, expected 'Queer: Bogotart', got 'Bogotart - Queer | Česká televize').

Seems to work here. Any chance you are hitting #2043?

[dirkf]

Satisfyingly, or not, I have a similar result (test 0) with my back-port to yt-dl, which led me to check the tests in yt-dlp.

In the browser with JS disabled, getPlaylistUrl, which is necessary for either of the attempts to get type, doesn't appear in the page: maybe it's been punted into some JS import.