chore: add traceback info to the failed to send message (#14299)

## Checklist
- [X] PR author has checked that all the criteria below are met
- The PR description includes an overview of the change
- The PR description articulates the motivation for the change
- The change includes tests OR the PR description describes a testing
strategy
- The PR description notes risks associated with the change, if any
- Newly-added code is easy to change
- The change follows the [library release note
guidelines](https://ddtrace.readthedocs.io/en/stable/releasenotes.html)
- The change includes or references documentation updates if necessary
- Backport labels are set (if
[applicable](https://ddtrace.readthedocs.io/en/latest/contributing.html#backporting))

## Reviewer Checklist
- [x] Reviewer has checked that all the criteria below are met 
- Title is accurate
- All changes are related to the pull request's stated goal
- Avoids breaking
[API](https://ddtrace.readthedocs.io/en/stable/versioning.html#interfaces)
changes
- Testing strategy adequately addresses listed risks
- Newly-added code is easy to change
- Release note makes sense to a user of the library
- If necessary, author has acknowledged and discussed the performance
implications of this PR as reported in the benchmarks PR comment
- Backport labels are set in a manner that is consistent with the
[release branch maintenance
policy](https://ddtrace.readthedocs.io/en/latest/contributing.html#backporting)

Signed-off-by: Juanjo Alvarez <juanjo.alvarezmartinez@datadoghq.com>

Author: juanjux

.gitlab/benchmarks/bp-runner.microbenchmarks.fail-on-breach.yml

@@ -1089,7 +1089,7 @@ experiments:
               - max_rss_usage < 34.00 MB
           - name: telemetryaddmetric-1-rate-metrics-100-times
             thresholds:
-              - execution_time < 0.23 ms
+              - execution_time < 0.24 ms
               - max_rss_usage < 34.00 MB
           - name: telemetryaddmetric-100-count-metrics-100-times
             thresholds:

ddtrace/internal/writer/writer.py

@@ -443,6 +443,7 @@ def _flush_single_payload(
                     n_traces,
                     self._intake_endpoint(client),
                     self.RETRY_ATTEMPTS,
+                    exc_info=True,
                 )
         finally:
             self._metrics_dist("http.sent.bytes", len(encoded))

tests/integration/test_integration.py

@@ -107,6 +107,7 @@ def test_uds_wrong_socket_path():
                 1,
                 "unix:///tmp/ddagent/nosockethere/{}/traces".format(encoding if encoding else "v0.5"),
                 3,
+                exc_info=True,
             )
         ]
     log.error.assert_has_calls(calls)
@@ -379,6 +380,7 @@ def test_trace_generates_error_logs_when_trace_agent_url_invalid():
                 1,
                 "http://localhost:8125/{}/traces".format(encoding if encoding else "v0.5"),
                 3,
+                exc_info=True,
             )
         ]
     log.error.assert_has_calls(calls)