Don't log traceback for http exceptions

[TheTechromancer]

Logging tracebacks for web exceptions results in a lot of overhead:

2023-12-22 20:52:33,248 [TRACE] bbot.core.helpers.web web.py:619 Unhandled exception with request to URL: https://evilcorp.com/common/admin/Calendar/Telerik.Web.UI.DialogHandler.aspx?dp=1: 
2023-12-22 20:52:33,249 [TRACE] bbot.core.helpers.web web.py:620 Traceback (most recent call last):
  File "/root/.local/share/virtualenvs/bbot_dev-KnMjRjwb/lib/python3.10/site-packages/anyio/_core/_tasks.py", line 115, in fail_after
    yield cancel_scope
  File "/root/.local/share/virtualenvs/bbot_dev-KnMjRjwb/lib/python3.10/site-packages/httpcore/_synchronization.py", line 125, in wait
    await self._anyio_event.wait()
  File "/root/.local/share/virtualenvs/bbot_dev-KnMjRjwb/lib/python3.10/site-packages/anyio/_backends/_asyncio.py", line 1616, in wait
    await self._event.wait()
  File "/usr/lib/python3.10/asyncio/locks.py", line 214, in wait
    await fut
asyncio.exceptions.CancelledError: Cancelled by cancel scope 7f3c31ccc970

During handling of the above exception, another exception occurred:

Traceback (most recent call last):
  File "/root/.local/share/virtualenvs/bbot_dev-KnMjRjwb/lib/python3.10/site-packages/httpcore/_exceptions.py", line 10, in map_exceptions
    yield
  File "/root/.local/share/virtualenvs/bbot_dev-KnMjRjwb/lib/python3.10/site-packages/httpcore/_synchronization.py", line 124, in wait
    with anyio.fail_after(timeout):
  File "/usr/lib/python3.10/contextlib.py", line 153, in __exit__
    self.gen.throw(typ, value, traceback)
  File "/root/.local/share/virtualenvs/bbot_dev-KnMjRjwb/lib/python3.10/site-packages/anyio/_core/_tasks.py", line 118, in fail_after
    raise TimeoutError
TimeoutError

The above exception was the direct cause of the following exception:

Traceback (most recent call last):
  File "/root/.local/share/virtualenvs/bbot_dev-KnMjRjwb/lib/python3.10/site-packages/httpcore/_async/connection_pool.py", line 233, in handle_async_request
    connection = await status.wait_for_connection(timeout=timeout)
  File "/root/.local/share/virtualenvs/bbot_dev-KnMjRjwb/lib/python3.10/site-packages/httpcore/_async/connection_pool.py", line 35, in wait_for_connection
    await self._connection_acquired.wait(timeout=timeout)
  File "/root/.local/share/virtualenvs/bbot_dev-KnMjRjwb/lib/python3.10/site-packages/httpcore/_synchronization.py", line 123, in wait
    with map_exceptions(anyio_exc_map):
  File "/usr/lib/python3.10/contextlib.py", line 153, in __exit__
    self.gen.throw(typ, value, traceback)
  File "/root/.local/share/virtualenvs/bbot_dev-KnMjRjwb/lib/python3.10/site-packages/httpcore/_exceptions.py", line 14, in map_exceptions
    raise to_exc(exc) from exc
httpcore.PoolTimeout

[TheTechromancer]

Fixed in #937.