fix(openai): guard client/openai access [backport 3.11] (#14238)

Backport 030b83c from #14186 to 3.11.

Closes #14168.

Adds a safe access to `OpenAI/AsyncOpenAI._client` in the openai
integration. Previously if the client was never initialized, it would
raise an error (according to issue).

Waiting on a better reproduction case from #14168 to add a regression
test.

## 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)

Co-authored-by: Yun Kim <[email protected]>
Co-authored-by: Sam Brenner <[email protected]>

Author: 3 people

ddtrace/llmobs/_integrations/openai.py

@@ -75,9 +75,9 @@ def _is_provider(self, span, provider):
         """Check if the traced operation is from the given provider."""
         base_url = None
         if parse_version(self._openai.version.VERSION) >= (1, 0, 0):
-            base_url = self._client._base_url
+            base_url = getattr(self._client, "_base_url", None)
         else:
-            base_url = self._openai.api_base
+            base_url = getattr(self._openai, "api_base", None)
         base_url = str(base_url) if base_url else None
         if not base_url or not isinstance(base_url, str):
             return False

releasenotes/notes/fix-openai-client-does-not-exist-06572c76555339a7.yaml

@@ -0,0 +1,4 @@
+---
+fixes:
+  - |
+    openai: Resolves an issue where an uninitialized ``OpenAI/AsyncOpenAI`` client would result in an ``AttributeError``.