Fix openai-agents import (#5132)

### Description
"agents" is too generic a name, and we're using it to determine whether
someone has openai-agents installed.

#### Issues
Closes #5129

#### Reminders
- Please add tests to validate your changes, and lint your code using
`tox -e linters`.
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commit](https://develop.sentry.dev/engineering-practices/commit-messages/#type)
style (`feat:`, `fix:`, `ref:`, `meta:`)
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Author: sentrivana

sentry_sdk/integrations/openai_agents/__init__.py

@@ -9,7 +9,13 @@
 )
 
 try:
+    # "agents" is too generic. If someone has an agents.py file in their project
+    # or another package that's importable via "agents", no ImportError would not
+    # be thrown and the integration would enable itself even if openai-agents is
+    # not installed. That's why we're adding the second, more specific import
+    # after it, even if we don't use it.
     import agents
+    from agents.run import DEFAULT_AGENT_RUNNER
 
 except ImportError:
     raise DidNotEnable("OpenAI Agents not installed")