[5.8] Relax version requirement for swift-argument-parser#1570

DougGregor merged 1 commit intoswiftlang:release/5.8swiftlang/swift-syntax:release/5.8from

ahoppen:ahoppen/5.8/argument-parser-dependencyahoppen/swift-syntax:ahoppen/5.8/argument-parser-dependencyCopy head branch name to clipboard