It fails on the testbot now because of the additional tests that were committed, I'll fix this.
Note that it doesn't fail when VA-API plugins are used because `vaapidecodebin` is actually matched first, and it includes a video format conversion element. I think we don't want that anyway, and also we don't want VA-API plugins for the moment because they will ignore our alignment requirements, so I think I'll make sure we don't match the plugins first.