[python] support enum type for array encode

[msyyc]

Auto PR for microsoft/typespec#9407

[msyyc]

@copilot apply https://github.com/microsoft/typespec/pull/9407/files#diff-76afd6a8715b0f455d980b871d8ecede16ad42a1e3f01a102fdeaf89a7fe371a to

autorest.python/packages/typespec-python/test/generic_mock_api_tests/asynctests/test_encode_array_async.py

Line 3 in fc176b9

# Licensed under the MIT License. See License.txt in the project root for

and apply https://github.com/microsoft/typespec/pull/9407/files#diff-f1f262fa62cde2b1d7871318ab156966fa416e4361a282b82a217d78b1bf6b09 to https://github.com/Azure/autorest.python/blob/fc176b928865f58eb6ed3cb378cddf63f0c85404/packages/typespec-python/test/generic_mock_api_tests/test_encode_array.py

NOTE:

• DO run python -m black -l 120 for your changed files.

[Copilot]

@msyyc I've opened a new pull request, #3303, to work on those changes. Once the pull request is ready, I'll request review from you.