Insufficient mocking in TestGenericHardwareManager

Noticing some more errors that may definitely be a WSL issue:

```
ironic_python_agent.tests.unit.test_hardware.TestGenericHardwareManager.test_erase_devices_metadata
---------------------------------------------------------------------------------------------------

Captured traceback:
~~~~~~~~~~~~~~~~~~~
    Traceback (most recent call last):

      File "/usr/lib/python3.10/unittest/mock.py", line 1379, in patched
    return func(*newargs, **newkeywargs)

      File "/home/bbgoddess/mlh-gresearch/ironic-python-agent/ironic_python_agent/tests/unit/test_hardware.py", line 2422, in test_erase_devices_metadata
    self.assertEqual([mock.call('/dev/sda1', self.node['uuid']),

      File "/home/bbgoddess/mlh-gresearch/ironic-python-agent/.tox/py3/lib/python3.10/site-packages/testtools/testcase.py", line 394, in assertEqual
    self.assertThat(observed, matcher, message)

      File "/home/bbgoddess/mlh-gresearch/ironic-python-agent/.tox/py3/lib/python3.10/site-packages/testtools/testcase.py", line 481, in assertThat
    raise mismatch_error

    testtools.matchers._impl.MismatchError: !=:
reference = [call('/dev/sda1', 'dda135fb-732d-4742-8e72-df8f3199d244'),
 call('/dev/sda', 'dda135fb-732d-4742-8e72-df8f3199d244'),
 call('/dev/md0', 'dda135fb-732d-4742-8e72-df8f3199d244')]
actual = [call('/dev/md0', 'dda135fb-732d-4742-8e72-df8f3199d244')]

Captured pythonlogging:
~~~~~~~~~~~~~~~~~~~~~~~
     WARNING [root] Could not determine if /dev/md0 is aread-only device. Error: [Errno 2] No such file or directory: '/sys/block/md/ro'
```

There are about 20 that are similar to this. Since this is all under the hood of the same core issue of WSL, I'll take a look at it.

I believe many of those will go away if you mock out those methods; in both cases, they're triggering the code paths in:

GenericHardwareManager._is_read_only_device
GenericHardwareManager._is_virtual_media_device

Which fail because they are not mocked. If you add mocking, similar to that used to mock GenericHardwareManager._is_linux_raid_member here: https://opendev.org/openstack/ironic-python-agent/src/branch/master/ironic_python_agent/tests/unit/test_hardware.py#L1710 you should solve them.

I expect you to have to add this mock to several tests (it's likely all 20 failures are related to this; but I'm not certain yet). The specific things I look for are: BlockDeviceEraseError exceptions in the traceback (none on the one you posted), or a message about being unable to read a file in /sys/ (this is present in your test failure) -- it's a red flag because at no point should IPA unit tests be reading *anything* on your actual disk.

I see, thank you. Currently, I am incorporating the necessary mocks into the specific test cases highlighted in the tracebacks.

I've gone ahead and marked + added mocks to the necessary tests, but it seems that there are unrelated errors as well, specifically two stand out to me the most. I will also go ahead and do my own research + debugging.

```
ironic_python_agent.tests.unit.test_hardware.TestGenericHardwareManager.test_erase_block_device_ata_frozen
----------------------------------------------------------------------------------------------------------

Captured traceback:
~~~~~~~~~~~~~~~~~~~
    Traceback (most recent call last):

      File "/usr/lib/python3.10/unittest/mock.py", line 1379, in patched
    return func(*newargs, **newkeywargs)

      File "/home/bbgoddess/mlh-gresearch/ironic-python-agent/ironic_python_agent/tests/unit/test_hardware.py", line 2166, in test_erase_block_device_ata_frozen
    self.assertRaises(

      File "/home/bbgoddess/mlh-gresearch/ironic-python-agent/.tox/py3/lib/python3.10/site-packages/testtools/testcase.py", line 468, in assertRaises
    self.assertThat(our_callable, matcher)

      File "/home/bbgoddess/mlh-gresearch/ironic-python-agent/.tox/py3/lib/python3.10/site-packages/testtools/testcase.py", line 481, in assertThat
    raise mismatch_error

    testtools.matchers._impl.MismatchError: <bound method GenericHardwareManager.erase_block_device of <ironic_python_agent.hardware.GenericHardwareManager object at 0x7ffa76185fc0>> returned None

```

As well as,
```
ironic_python_agent.tests.unit.test_hardware.TestGenericHardwareManager.test_erase_devices_metadata_error
---------------------------------------------------------------------------------------------------------

Captured traceback:
~~~~~~~~~~~~~~~~~~~
    Traceback (most recent call last):

      File "/usr/lib/python3.10/unittest/mock.py", line 1379, in patched
    return func(*newargs, **newkeywargs)

      File "/home/bbgoddess/mlh-gresearch/ironic-python-agent/ironic_python_agent/tests/unit/test_hardware.py", line 2533, in test_erase_devices_metadata_error
    self.assertEqual([mock.call('/dev/sdb', self.node['uuid']),

      File "/home/bbgoddess/mlh-gresearch/ironic-python-agent/.tox/py3/lib/python3.10/site-packages/testtools/testcase.py", line 394, in assertEqual
    self.assertThat(observed, matcher, message)

      File "/home/bbgoddess/mlh-gresearch/ironic-python-agent/.tox/py3/lib/python3.10/site-packages/testtools/testcase.py", line 481, in assertThat
    raise mismatch_error

    testtools.matchers._impl.MismatchError: !=:
reference = [call('/dev/sdb', 'dda135fb-732d-4742-8e72-df8f3199d244'),
 call('/dev/sda', 'dda135fb-732d-4742-8e72-df8f3199d244')]
actual = [call('/dev/sdb', 'dda135fb-732d-4742-8e72-df8f3199d244')]

Captured pythonlogging:
~~~~~~~~~~~~~~~~~~~~~~~
       ERROR [root] Failed to erase the metadata on device "/dev/sdb". Error: Unexpected error while running command.
Command: None
Exit code: -
Stdout: 'Booo00000ooommmmm'
Stderr: None
```

Let's get your attempted fix into gerrit so I can see and comment on the actual code; we'll figure it out :)

Unsure why https://review.opendev.org/c/openstack/ironic-python-agent/+/897611 isn't updating here; I believe the syntax in the commit message is correct. Either way, fix proposed there.

Awesome, are we ready to close this bug and mark it as Fix-Committed?

It can't be closed and marked as fixed until after the change merges; I have a +2 on the change; you need an additional review before it can land.