maintaining possible_ends list for next speech segment

[shashank14k]

The possible_ends list contains a tuple of (end_idx, silence_at_the_idx) which is used to find an optimal cut once max_speech_segment is reached. Previously, it was being set to an empty list after a segment was appended. However, the tuples where end_idx > next_start can be retained. For example:

1. possible_ends = [(862720, 1280), (888832, 2560), (950784, 1280)] and use_max_poss_sil_at_max_speech == True
2. The segment will be cut at 888832 and the next segment will start at next_start = (888832 + 2560) < 950784
3. So, (950784, 1280) should be retained for the subsquent iteration

[Purfview]

This is not OK. 😁