fallbackswitch now supports multiple sink pads, and on a timeout of the
active pad, it will automatically switch to the next lowest priority pad
that has data available.
fallbackswitch sink pads follow the `sink_%u` template and have
`priority` as a pad property.
Co-authored-by: Vivia Nikolaidou <vivia.nikolaidou@ltnglobal.com>
This is a wrapper around uridecodebin3 and fallbackswitch that allows to
switch to a still frame on errors and automatically retries the source
in the background on errors until a given retry timeout is reached.