Fix ResourceWarning due to unclosed file resource.

[tirkarthi]

Fixes below warnings that were originally found in CPython test suite.

============================================================================= warnings summary ==============================================================================
importlib_resources/tests/test_resource.py::ResourceFromZipsTest01::test_as_file_directory
  /home/karthikeyan/stuff/python/importlib_resources/importlib_resources/_common.py:206: ResourceWarning: unclosed file <_io.BufferedWriter name='/tmp/tmpekn15a6u/ziptestdata/utf-16.file'>
    child.open('wb').write(source.read_bytes())
  Enable tracemalloc to get traceback where the object was allocated.
  See https://docs.pytest.org/en/stable/how-to/capture-warnings.html#resource-warnings for more info.

importlib_resources/tests/test_resource.py::ResourceFromZipsTest01::test_as_file_directory
  /home/karthikeyan/stuff/python/importlib_resources/importlib_resources/_common.py:206: ResourceWarning: unclosed file <_io.BufferedWriter name='/tmp/tmpekn15a6u/ziptestdata/utf-8.file'>
    child.open('wb').write(source.read_bytes())
  Enable tracemalloc to get traceback where the object was allocated.
  See https://docs.pytest.org/en/stable/how-to/capture-warnings.html#resource-warnings for more info.

importlib_resources/tests/test_resource.py::ResourceFromZipsTest01::test_as_file_directory
  /home/karthikeyan/stuff/python/importlib_resources/importlib_resources/_common.py:206: ResourceWarning: unclosed file <_io.BufferedWriter name='/tmp/tmpekn15a6u/ziptestdata/__init__.py'>
    child.open('wb').write(source.read_bytes())
  Enable tracemalloc to get traceback where the object was allocated.
  See https://docs.pytest.org/en/stable/how-to/capture-warnings.html#resource-warnings for more info.

importlib_resources/tests/test_resource.py::ResourceFromZipsTest01::test_as_file_directory
  /home/karthikeyan/stuff/python/importlib_resources/importlib_resources/_common.py:206: ResourceWarning: unclosed file <_io.BufferedWriter name='/tmp/tmpekn15a6u/ziptestdata/binary.file'>
    child.open('wb').write(source.read_bytes())
  Enable tracemalloc to get traceback where the object was allocated.
  See https://docs.pytest.org/en/stable/how-to/capture-warnings.html#resource-warnings for more info.

importlib_resources/tests/test_resource.py::ResourceFromZipsTest01::test_as_file_directory
  /home/karthikeyan/stuff/python/importlib_resources/importlib_resources/_common.py:206: ResourceWarning: unclosed file <_io.BufferedWriter name='/tmp/tmpekn15a6u/ziptestdata/subdirectory/__init__.py'>
    child.open('wb').write(source.read_bytes())
  Enable tracemalloc to get traceback where the object was allocated.
  See https://docs.pytest.org/en/stable/how-to/capture-warnings.html#resource-warnings for more info.

importlib_resources/tests/test_resource.py::ResourceFromZipsTest01::test_as_file_directory
  /home/karthikeyan/stuff/python/importlib_resources/importlib_resources/_common.py:206: ResourceWarning: unclosed file <_io.BufferedWriter name='/tmp/tmpekn15a6u/ziptestdata/subdirectory/binary.file'>
    child.open('wb').write(source.read_bytes())
  Enable tracemalloc to get traceback where the object was allocated.
  See https://docs.pytest.org/en/stable/how-to/capture-warnings.html#resource-warnings for more info.

-- Docs: https://docs.pytest.org/en/stable/how-to/capture-warnings.html

[jaraco]

I wonder why this test suite doesn't emit the warnings. Aah. So it seems Python ignores ResourceWarnings by default. I've opened jaraco/skeleton#73 to ensure this issue doesn't occur in any other skeleton-backed projects.

[jaraco]

Released as v5.10.1. Will get synced with CPython in the future. I'll try not to let it linger into 2023.

[tirkarthi]

Thanks @jaraco