Print exception trace for functions submitted to thread_pool (#32030)

* Print exception trace in thread_pool

* Fix sanity test

* fix format

* Change traceback.print_exception to traceback.print_exc

src/python/grpcio/grpc/_server.py

@@ -21,6 +21,7 @@ import enum
 import logging
 import threading
 import time
+import traceback
 from typing import (Any, Callable, Iterable, Iterator, List, Mapping, Optional,
                     Sequence, Set, Tuple, Union)
 
@@ -624,6 +625,8 @@ def _unary_response_in_pool(
                     rpc_event, state, response, response_serializer)
                 if serialized_response is not None:
                     _status(rpc_event, state, serialized_response)
+    except Exception:  # pylint: disable=broad-except
+        traceback.print_exc()
     finally:
         cygrpc.uninstall_context()
 
@@ -662,6 +665,8 @@ def _stream_response_in_pool(
                 if proceed:
                     _send_message_callback_to_blocking_iterator_adapter(
                         rpc_event, state, send_response, response_iterator)
+    except Exception:  # pylint: disable=broad-except
+        traceback.print_exc()
     finally:
         cygrpc.uninstall_context()