downgrade batches for bindparam() in SET

downgrade batches for bindparam() in SET

Fixed issue where :meth:`_postgresql.Insert.on_conflict_do_update`
using parametrized bound parameters in the ``set_`` clause would fail
when used with executemany batching. For dialects that use the
``use_insertmanyvalues_wo_returning`` optimization (psycopg2),
insertmanyvalues is now disabled when there is an ON CONFLICT clause.
For cases with RETURNING, row-at-a-time mode is used when the SET
clause contains parametrized bindparams (bindparams that receive
values from the parameters dict), ensuring each row's parameters are
correctly applied. ON CONFLICT statements using expressions like
``excluded.<column>`` continue to batch normally.

Fixed issue where :meth:`_sqlite.Insert.on_conflict_do_update`
using parametrized bound parameters in the ``set_`` clause would fail
when used with executemany batching. Row-at-a-time mode is now used
for ON CONFLICT statements with RETURNING that contain parametrized
bindparams, ensuring each row's parameters are correctly applied. ON
CONFLICT statements using expressions like ``excluded.<column>``
continue to batch normally.

Fixes: #13130
Change-Id: I0c5a9142401c745d38e58d071c16e53610f9bfea
(cherry picked from commit 5b2e7aae01cc2e55e68a8445569ee709b17715dd)