appsrc: disable automatic eos

I have a "src -> appsrc <--> appsink" setup where the source consecutively decodes media files. Each media is preceded by a segment event updating the segment base so the stream time stays continous.

This does not work because appsrc stops processing data after the first media is done playing as appsrc considers itself as done because of the first segment. The segment for the next item is still in appsrc queue so has not been handled by basesrc yet.

Disabling automatic eos fixes this use case.

Not sure if this should be the default or if we should add a property to control it?