Deepfreeze essential parts of the encodings module. ### Description

This is a split off from #3582.

Deepfreeze essential parts of encodings module (encodings.\__init__, encodings.utf_8, and encodings.aliases), which is required during the Python bootstrap.

from pytest_pyodide import run_in_pyodide


@run_in_pyodide(packages=["test"], pytest_assert_rewrites=False)
def test_test(selenium):
    # this is tested in test_core_python.py instead
    pass

from pytest_pyodide import run_in_pyodide


@run_in_pyodide(packages=["test"], pytest_assert_rewrites=False)
def test_test(selenium):
    # this is tested in test_core_python.py instead
    pass
