fix: remove .upper() mutation on document ID in _row_to_document

Document IDs should be returned exactly as stored. The .upper() call
was silently mutating lowercase or mixed-case IDs on retrieval.

Addresses review feedback from @davidsbatista.

Author: fede-kamel

integrations/oracle/src/haystack_integrations/document_stores/oracle/document_store.py

@@ -484,7 +484,7 @@ def _row_to_document(row: tuple, *, with_score: bool = False) -> Document:
             meta = {}
 
         return Document(
-            id=raw_id.upper(),
+            id=raw_id,
             content=text,
             meta=meta,
             score=float(score) if score is not None else None,