Create unit-tests for the engine checking the correctness about kernel-hardening-checker

[a13xp0p0v]

Good. This task is completed.

Unit-tests for the kconfig-hardened-check engine are created:
kconfig_hardened_check/test_engine.py

CI performs unit-testing on each repository push:
https://github.com/a13xp0p0v/kconfig-hardened-check/actions/workflows/engine_unit-test.yml

These unit-tests check the correctness of the engine results and cover 100% of the engine code.

Reverting the aforementioned fix d006bfa is detected by these unit-tests:

======================================================================
FAIL: test_simple_kconfig (kconfig_hardened_check.test_engine.TestEngine)
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Traceback (most recent call last):
  File "/home/a13x/land/Develop/Linux_Kernel/kconfig-hardened-check/kconfig_hardened_check/test_engine.py", line 130, in test_simple_kconfig
    self.assertEqual(
AssertionError: Lists differ: [['CO[701 chars]8', 'OK: is not off, "off"'], ['CONFIG_NAME_9'[169 chars]nd']] != [['CO[701 chars]8', 'FAIL: is off'], ['CONFIG_NAME_9', 'kconfi[160 chars]nd']]

First differing element 7:
['CON[25 chars]is not off', 'decision_8', 'reason_8', 'OK: is not off, "off"']
['CON[25 chars]is not off', 'decision_8', 'reason_8', 'FAIL: is off']