Merge pyodide_py into python_stdlib.zip. ### Description

Merges pyodide_py.tar into python_stdlib.zip. This reduces the number of network requests during the initialization.

The original intention of splitting pyodide_py.tar from pyodide.asm.data was to give users an option to provide custom files (#2023), which is now available by modifying python_stdlib.zip directly. So I think there is no reason to have both python_stdlib.zip and pyodide_py.tar.

### Checklists

- [x] Add a [CHANGELOG](https://github.com/pyodide/pyodide/blob/main/docs/project/changelog.md) entry
- [x] Add / update tests

package:
  name: pycryptodome
  version: 3.16.0
  top-level:
    - Crypto
source:
  url: https://files.pythonhosted.org/packages/0d/66/5e4a14e91ffeac819e6888037771286bc1b86869f25d74d60bc4a61d2c1e/pycryptodome-3.16.0.tar.gz
  sha256: 0e45d2d852a66ecfb904f090c3f87dc0dfb89a499570abad8590f10d9cffb350
build:
  exports: requested
about:
  home: https://www.pycryptodome.org
  PyPI: https://pypi.org/project/pycryptodome
  summary: Cryptographic library for Python
  license: BSD, Public Domain

package:
  name: pycryptodome
  version: 3.16.0
  top-level:
    - Crypto
source:
  url: https://files.pythonhosted.org/packages/0d/66/5e4a14e91ffeac819e6888037771286bc1b86869f25d74d60bc4a61d2c1e/pycryptodome-3.16.0.tar.gz
  sha256: 0e45d2d852a66ecfb904f090c3f87dc0dfb89a499570abad8590f10d9cffb350
build:
  exports: requested
about:
  home: https://www.pycryptodome.org
  PyPI: https://pypi.org/project/pycryptodome
  summary: Cryptographic library for Python
  license: BSD, Public Domain
