Python 3.11 unit test failures

[Corey Bryant]

==============================
Failed 2 tests - output below:
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murano.tests.unit.engine.system.test_agent.TestExecutionPlan.test_file_line_endings
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Captured traceback:
~~~~~~~~~~~~~~~~~~~
    Traceback (most recent call last):

      File "/usr/lib/python3.11/unittest/mock.py", line 1369, in patched
    return func(*newargs, **newkeywargs)
           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

      File "/home/corey/pkg/antelope/upstream/murano/murano/tests/unit/engine/system/test_agent.py", line 677, in test_file_line_endings
    result = resources.string(script_file.name)
             ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

      File "/home/corey/pkg/antelope/upstream/murano/murano/tests/unit/engine/system/test_agent.py", line 652, in string
    return resource_manager.ResourceManager.string(
           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

      File "/home/corey/pkg/antelope/upstream/murano/murano/engine/system/resource_manager.py", line 61, in string
    with open(path, mode) as file:
         ^^^^^^^^^^^^^^^^

    ValueError: invalid mode: 'rU'

Captured pythonlogging:
~~~~~~~~~~~~~~~~~~~~~~~
    Key file %s does not exist. Message signing is disabled

murano.tests.unit.engine.test_mock_context_manager.TestMockManager.test_create_type_context
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Captured traceback:
~~~~~~~~~~~~~~~~~~~
    Traceback (most recent call last):

      File "/home/corey/pkg/antelope/upstream/murano/murano/tests/unit/engine/test_mock_context_manager.py", line 76, in test_create_type_context
    p.start()

      File "/usr/lib/python3.11/unittest/mock.py", line 1585, in start
    result = self.__enter__()
             ^^^^^^^^^^^^^^^^

      File "/usr/lib/python3.11/unittest/mock.py", line 1437, in __enter__
    original, local = self.get_original()
                      ^^^^^^^^^^^^^^^^^^^

      File "/usr/lib/python3.11/unittest/mock.py", line 1410, in get_original
    raise AttributeError(

    AttributeError: <module 'inspect' from '/usr/lib/python3.11/inspect.py'> does not have the attribute 'getargspec'

[OpenStack Infra (hudson-openstack)]

Related fix proposed to branch: master
Review: https://review.opendev.org/c/openstack/murano/+/869880

[OpenStack Infra (hudson-openstack)]

Change abandoned by "Ghanshyam <email address hidden>" on branch: master
Review: https://review.opendev.org/c/openstack/murano/+/869880
Reason: Murano project has been retired https://review.opendev.org/c/openstack/governance/+/919358