fix commit/rollback markers

fix typos

Author: rekby

tests/aio/test_tx.py

@@ -85,7 +85,6 @@ async def test_tx_snapshot_ro(driver, database):
 
     await ro_tx.commit()
 
-    ro_tx = session.transaction(tx_mode=ydb.SnapshotReadOnly())
     with pytest.raises(ydb.issues.GenericError) as exc_info:
         await ro_tx.execute("UPDATE `test` SET value = value + 1")
     assert "read only transaction" in exc_info.value.message

tests/table/test_tx.py

@@ -80,7 +80,6 @@ def test_tx_snapshot_ro(driver_sync, database):
 
     ro_tx.commit()
 
-    ro_tx = session.transaction(tx_mode=ydb.SnapshotReadOnly())
     with pytest.raises(ydb.issues.GenericError) as exc_info:
         ro_tx.execute("UPDATE `test` SET value = value + 1")
     assert "read only transaction" in exc_info.value.message

ydb/table.py

@@ -2459,8 +2459,7 @@ def async_commit(self, settings=None):
 
         :return: A future of commit call
         """
-        self._check_split()
-        self._finished = True
+        self._set_finish(self._COMMIT)
 
         if self._tx_state.tx_id is None and not self._tx_state.dead:
             return _utilities.wrap_result_in_future(self)
@@ -2485,8 +2484,7 @@ def async_rollback(self, settings=None):
 
         :return: A future of rollback call
         """
-        self._check_split()
-        self._finished = True
+        self._set_finish(self._ROLLBACK)
 
         if self._tx_state.tx_id is None and not self._tx_state.dead:
             return _utilities.wrap_result_in_future(self)