[saifmodan2006]

Problem

For spies whose mock is a MagicMock (classmethods, staticmethods, builtins and classes), calling spy.reset_mock(side_effect=True) clears the mock's side_effect. Because the spy relies on side_effect to invoke the wrapped implementation, subsequent calls return a MagicMock rather than calling through to the spied code (#636).

Solution

Override reset_mock on spy objects returned by mocker.spy:

1. Call the original reset_mock(*args, **kwargs) to reset mock call history.
2. Reset recorded spy call attributes (spy_return, spy_return_list, etc.).
3. Restore spy_obj.side_effect = wrapped when side_effect=True is passed, restoring the spied code invocation.

Validation

• Added parameterized unit tests in tests/test_pytest_mock.py covering classmethod, staticmethod, builtin, and class spies after spy.reset_mock(return_value=..., side_effect=...).
• Added test verifying custom side_effect override on a spy is cleared by spy.reset_mock(side_effect=True).
• Added test verifying recorded spy attributes on function/method spies are reset by spy.reset_mock().
• Added changelog entry in CHANGELOG.rst and updated docs/usage.rst.
• Verified all 86 spy tests pass.

Closes #636