When `pr-agent` is reviewing a long list of messages, a TypeError is thrown on the line
```python
for message in reversed(discussion_messages):
```
When reviewing the PyGithub library, the recommend an alternate syntax for iterating a paginated list in reverse.
https://github.com/PyGithub/PyGithub/blob/v1.59.0/github/PaginatedList.py#L122-L125
```
If you want to iterate in reversed order, just do::
for repo in user.get_repos().reversed:
print(repo.name)
```
And here's a copy of the actual traceback
```
Traceback (most recent call last):
File "/app/pr_agent/servers/github_action_runner.py", line 68, in <module>
asyncio.run(run_action())
File "/usr/local/lib/python3.10/asyncio/runners.py", line 44, in run
return loop.run_until_complete(main)
File "/usr/local/lib/python3.10/asyncio/base_events.py", line 649, in run_until_complete
return future.result()
File "/app/pr_agent/servers/github_action_runner.py", line 64, in run_action
await PRAgent().handle_request(pr_url, body)
File "/app/pr_agent/agent/pr_agent.py", line 19, in handle_request
await PRReviewer(pr_url, is_answer=True).review()
File "/app/pr_agent/tools/pr_reviewer.py", line 49, in __init__
answer_str, question_str = self._get_user_answers()
File "/app/pr_agent/tools/pr_reviewer.py", line 253, in _get_user_answers
for message in reversed(discussion_messages):
TypeError: object of type 'PaginatedList' has no len()
```
