v0.2.3

<!-- Release notes generated using configuration in .github/release.yml at v0.2.3 -->

What's Changed

• Add MachineRootfs type with SizeGB field by @dangra in https://github.com/superfly/fly-go/pull/206

Full Changelog: https://github.com/superfly/fly-go/compare/v0.2.2...v0.2.3