e2e: test the hook-sdist and hook-prebuilt source profiles #1420

Problem

e2e/test_build_source_config.sh covers two source: profiles (github-tag-git and pypi-download). Neither hook profile (hook-sdist, hook-prebuilt) has an end-to-end test, although they are the migration path for packages that keep their plugins.

e2e/test_prebuilt_wheel_hook.sh already tests a download_source hook with the old pre_built settings.

Fix

Add e2e cases:

• hook-prebuilt with index_url and a download_source hook (can reuse the plugin from test_prebuilt_wheel_hook.sh)
• hook-sdist with a get_resolver_provider and/or download_source hook

Each should check that the hooks were called and what the build order records.

Related: #1416 (the rule that hooks require a hook-* profile). Non-blocking for #1414. Reported in review of #1414.