chore(fix-2530): document duck typing pattern in catalog fixtures

Add inline comments to catalog and catalog_with_warehouse fixtures explaining
the hasattr(cat, 'close') pattern. This clarifies that:
- Not all catalog implementations provide close() (REST, Glue catalogs don't)
- SQLCatalog does provide close() for proper connection cleanup
- The pattern prevents AttributeError while supporting resource cleanup
- This is essential for Python 3.13+ ResourceWarning prevention (issue #2530)

This helps future contributors understand why the pattern is necessary
and when they should update it if new catalog types are added.

Co-Authored-By: Claude Haiku 4.5 <noreply@anthropic.com>

Author: williamacostalora

tests/conftest.py

@@ -3149,6 +3149,10 @@ def catalog(request: pytest.FixtureRequest, tmp_path: Path) -> Generator[Catalog
     yield cat
     if hasattr(cat, "destroy_tables"):
         cat.destroy_tables()
+    # Use duck typing to safely call close() only if available.
+    # Not all catalog implementations (e.g., REST, Glue) have close(), but SQLCatalog does.
+    # This pattern prevents AttributeError while supporting proper resource cleanup for
+    # catalogs that manage connections. See issue #2530 for Python 3.13 ResourceWarning fix.
     if hasattr(cat, "close"):
         cat.close()
 
@@ -3163,6 +3167,10 @@ def catalog_with_warehouse(
     yield cat
     if hasattr(cat, "destroy_tables"):
         cat.destroy_tables()
+    # Use duck typing to safely call close() only if available.
+    # Not all catalog implementations (e.g., REST, Glue) have close(), but SQLCatalog does.
+    # This pattern prevents AttributeError while supporting proper resource cleanup for
+    # catalogs that manage connections. See issue #2530 for Python 3.13 ResourceWarning fix.
     if hasattr(cat, "close"):
         cat.close()