Before this fix we could only list messages of a thread if it was part of a `threading_enabled` channel or if the thread was set to `force`.
Due to our design of also using a thread id when this is just a chain of replies so we can switch from threading enabled to disabled at any time, we will allow `Chat:: ListChannelThreadMessages` to list the messages of any thread, the only important requirements are:
- having a thread id
- being able to access this thread
To allow this, this commit simply removes the check on `threading_enabled` or `force`.
5aefda1dee