[Pitch] List Swift Testing tags with swift test list --tags

Hello everyone, swift test --filter tag:<name> can already run Swift Testing tests by tag, but there is no way to see which tags a package uses. I'd like to propose swift test list --tags, which prints the unique tags used by a package's Swift Testing tests. The full proposal is below. Original issue: Add support for listing all test tags · Issue #8889 · swiftlang/swift-package-manager · GitHub Implementation (prototype): Add `--tags` option to list Swift Testing tags by letsgobjones · Pull R...