fix(temporal): Add httpcore to passthrough modules

This commit resolves an issue where using Mistral models within a
Temporal worker would fail due to `httpcore` not being available in the
sandboxed environment.

The `PydanticAIPlugin` has been updated to include `httpcore` in the
list of passthrough modules, ensuring its availability to the worker.

Fixes #3117

Author: Akos Bontovics

pydantic_ai_slim/pydantic_ai/durable_exec/temporal/__init__.py

@@ -62,6 +62,7 @@ def configure_worker(self, config: WorkerConfig) -> WorkerConfig:
                     'logfire',
                     'rich',
                     'httpx',
+                    'httpcore',
                     # Imported inside `logfire._internal.json_encoder` when running `logfire.info` inside an activity with attributes to serialize
                     'attrs',
                     # Imported inside `logfire._internal.json_schema` when running `logfire.info` inside an activity with attributes to serialize