flash_encryption_example: Remove unnecessary monkeypatch for the

flash_encryption pytest.
Earlier monkeypatching was done to add erase_partition functionality.
The required code has been added upstream in pytest-embedded

examples/security/flash_encryption/conftest.py

@@ -1,45 +0,0 @@
-# SPDX-FileCopyrightText: 2022 Espressif Systems (Shanghai) CO LTD
-# SPDX-License-Identifier: Apache-2.0
-
-import logging
-
-import pytest
-from _pytest.fixtures import FixtureRequest
-from _pytest.monkeypatch import MonkeyPatch
-from pytest_embedded_idf.serial import IdfSerial
-
-
-# This is a custom Serial Class to add the erase_flash functionality
-class FlashEncSerial(IdfSerial):
-
-    @IdfSerial.use_esptool
-    def erase_partition(self, partition_name: str) -> None:
-
-        if partition_name is None:
-            logging.error('Invalid arguments')
-            return
-
-        if not self.app.partition_table:
-            logging.error('Partition table not parsed.')
-            return
-
-        if partition_name in self.app.partition_table:
-            address = self.app.partition_table[partition_name]['offset']
-            size = self.app.partition_table[partition_name]['size']
-            logging.info('Erasing the partition {0} of size {1} at {2}'.format(partition_name, size, address))
-            self.stub.erase_region(address, size)
-        else:
-            logging.error('partition name {0} not found in app partition table'.format(partition_name))
-            return
-
-
-@pytest.fixture(scope='module')
-def monkeypatch_module(request: FixtureRequest) -> MonkeyPatch:
-    mp = MonkeyPatch()
-    request.addfinalizer(mp.undo)
-    return mp
-
-
-@pytest.fixture(scope='module', autouse=True)
-def replace_dut_class(monkeypatch_module: MonkeyPatch) -> None:
-    monkeypatch_module.setattr('pytest_embedded_idf.serial.IdfSerial', FlashEncSerial)