stream_bluray: do not demux_flush on angle change

A demux_flush can cause corruption and a slight A/V desync, whereas
without it the angle will simply change on the next keyframe, as is
intended for seamless branching. If users want an instant angle change
they can still restart playback and seek to the current position
through Lua.

player/command.c

@@ -8059,7 +8059,6 @@ void mp_option_run_callback(struct MPContext *mpctx, struct mp_option_callback *
         if (mpctx->playback_initialized && demuxer && demuxer->stream && strcmp(demuxer->stream->info->name, "bdvm/bluray")) {
             int angle = opts->stream_bluray_opts->angle - 1;
             stream_control(demuxer->stream, STREAM_CTRL_SET_ANGLE, &angle);
-            demux_flush(demuxer);
         }
     }
 #endif