0.12.5 Allow for workspaces containing only a package; --dry-run flag

What's Changed

• Allow for workspaces containing a package by @mikeger in #57
• 55: Flag --dry-run by @mikeger in #59

Full Changelog: 0.12.3...0.12.5

Binary artifactbundle

.binaryTarget(
  name: "xcode-selective-test",
  url: "https://github.com/mikeger/XcodeSelectiveTesting/releases/download/0.12.5/xcode-selective-test.artifactbundle.zip",
  checksum: "5af6d253d23a6b3a948337c9ff3c299cb2965af9580f01a4a3173f9de27ae629"
)