test: serve the whole-log fallback in the streamed log mocks (#1114)

Fixes a flaky
`test_actor_call_redirect_logs_to_default_logger_async[httpx2]` ([failed
run](https://github.com/apify/apify-client-python/actions/runs/38167530123/attempts/1)).

When `call()` finishes before the log stream delivers its first chunk,
`StreamedLog` reads the whole log with `GET /log?raw=true` (added in
#1084). The `mock_api` and `mock_api_failing_status_poll` fixtures
didn't serve that endpoint. In
`test_actor_call_returns_run_when_status_poll_fails_sync`, the sync
thread then retried the 500 with backoff, outlived the 5 s join in
`stop()`, and logged its error into the next test's `caplog` on the same
xdist worker.

Both fixtures now serve the whole log on that endpoint. Locally the
failure went from 2/10 to 0/40 with the two tests in CI order, and
`test_logging.py` under `-n auto` passed 30/30.

*✍️ Drafted by Claude Code*

Author: vdusek

tests/unit/test_logging.py

@@ -227,6 +227,10 @@ def mock_api(httpserver: HTTPServer) -> None:
     httpserver.expect_request(
         f'/v2/actor-runs/{_MOCKED_RUN_ID}/log', method='GET', query_string='stream=true&raw=true'
     ).respond_with_handler(_streaming_log_handler)
+    # A streamed log stopped before its first chunk falls back to reading the whole log.
+    httpserver.expect_request(
+        f'/v2/actor-runs/{_MOCKED_RUN_ID}/log', method='GET', query_string='raw=true'
+    ).respond_with_data(b''.join(_MOCKED_ACTOR_LOGS), content_type='application/octet-stream')
 
 
 @pytest.fixture
@@ -1137,6 +1141,9 @@ def _status_handler(request: Request) -> Response:
     httpserver.expect_request(
         f'/v2/actor-runs/{_MOCKED_RUN_ID}/log', method='GET', query_string='stream=true&raw=true'
     ).respond_with_handler(_streaming_log_handler)
+    httpserver.expect_request(
+        f'/v2/actor-runs/{_MOCKED_RUN_ID}/log', method='GET', query_string='raw=true'
+    ).respond_with_data(b''.join(_MOCKED_ACTOR_LOGS), content_type='application/octet-stream')
 
 
 @pytest.mark.usefixtures('mock_api_failing_status_poll', 'propagate_stream_logs')