1129817 - prepend process id and thread id if line is split

By including a unique identifier, it is possible to separate logs that are generated at the same time.

 [Bugzilla-1129817](https://bugzilla.redhat.com/show_bug.cgi?id=1129817)
So you could say,

```
if msg_id and not message_chunk.startswith(msg_id):
```