Add the BQ job usage tracking from LangChain (#17123)

- **Description:**
Add the BQ job usage tracking from LangChain

---------

Co-authored-by: Erick Friis <erick@langchain.dev>

libs/community/langchain_community/utils/google.py

@@ -0,0 +1,25 @@
+"""Utilities to use Google provided components."""
+
+from importlib import metadata
+from typing import Any, Optional
+
+
+def get_client_info(module: Optional[str] = None) -> Any:
+    r"""Returns a custom user agent header.
+
+    Args:
+        module (Optional[str]):
+            Optional. The module for a custom user agent header.
+    Returns:
+        google.api_core.gapic_v1.client_info.ClientInfo
+    """
+    from google.api_core.gapic_v1.client_info import ClientInfo
+
+    langchain_version = metadata.version("langchain")
+    client_library_version = (
+        f"{langchain_version}-{module}" if module else langchain_version
+    )
+    return ClientInfo(
+        client_library_version=client_library_version,
+        user_agent=f"langchain/{client_library_version}",
+    )