Add build-system configuration to lock-package

Adds a build-system section to the lock package pyproject.toml.

Does not change anything for people running with --build, just for those who generate the project and want to inspect/move it from there.

What's Changed

• Fix the help message for --ignore argument by @maresb in #27
• Add build system by @bneijt in #29

New Contributors

• @maresb made their first contribution in #27

Full Changelog: 0.4.4...0.4.5