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=["regex"])
def test_regex(selenium):
    import regex

    assert regex.search("o", "foo").end() == 2

from pytest_pyodide import run_in_pyodide


@run_in_pyodide(packages=["regex"])
def test_regex(selenium):
    import regex

    assert regex.search("o", "foo").end() == 2
