gh-158797: Update docs for test.support.import_helper

[DavidCEllis]

This PR adds documentation for previously undocumented functions, classes and arguments in test.support.import_helper.

Additions:

• add_module
• add_package
• create_module
• ensure_module_imported
• frozen_modules
• isolated_modules
• multi_interp_extensions_check
• ready_to_import

New/renamed arguments:

• CleanImport - added usefrozen keyword argument
• forget - module_name -> modname to match code
• import_fresh_module - added usefrozen, deprecated is keyword only
• make_legacy_pyc - added allow_compile

Left for now:

module_restored is currently left undocumented as on attempting to document it I realised that I don't think all branches work as intended.

In documenting the missing functions and classes I found it difficult to discover appropriate functions and so have added some subheadings and regrouped the functions and classes by some sense of functionality. This puts things like unload and forget which are similar with slight differences together for instance.

• Issue: Update the docs for test.support.import_helper #158797

[DavidCEllis]

This is what I get for accidentally clicking the update button.

[read-the-docs-community]

Documentation build overview

📚 cpython-previews | 🛠️ Build #34949964 | 📁 Comparing 0170e1b against main (cfd6cf7)

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1 file changed

± library/test.html