v0.3.0: CMake Updates, clang format

What's Changed

• Update container that is used in CI by @tmadlener in #7
• CMake: add ProjectConfig.cmake including version definition by @andresailer in #8
• [ci] add clang-format check by @vvolkl in #9

New Contributors

• @tmadlener made their first contribution in #7

Full Changelog: v0.2.0...v0.3.0