cda: fix bug, when cda link was in form cda.pl/video/[id]/vfilm

[gucio321]

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Description of your pull request and other information

This pull request fixes #28936 .
because my issue was closed, without any reason, and I wasn't able to find duplication I decided to fix this bug myself.
these chenges should fix bug, when URLs like https://cda.pl/video/[id]/vfilm was not downloaded
btw, I'm not a native python developer, so let me know, if there is another (better) solution of this problem.