There's a closed pull request on the void-packages repository

common/build-style/python3-pep517.sh: unpack wheels for testing
https://github.com/void-linux/void-packages/pull/42013

Description:
#### Testing the changes
- I tested the changes in this PR: **YES**

Python packages built with pep517 system occasionally require accessing distinfo files and/or entry points provided by the package for tests to run. Since these assets are packed inside the wheel generated in `do_build`, the target wheel is unpacked in `do_check` first so that the said artifacts are accessible during test runs.

Initially I unpacked the wheel during `do_build` with the `do_install` only copying the unarchived files (similar to the zig build style). That required patching pep517 templates with explicit `do_build` but no explicit `do_install`. There were only four such cases and it worked fine for me locally but maybe that was too big of a change so submitting this version for now instead.

The later commits are for demonstration purpose and not intended for merging. Those templates (and hopefully all others) still work fine as is.