gems: update async-dns requirement from ~> 1.3.0 to >= 1.3, < 1.5

Updates the requirements on [async-dns](https://github.com/socketry/async-dns) to permit the latest version.
- [Changelog](https://github.com/socketry/async-dns/blob/main/release.cert)
- [Commits](https://github.com/socketry/async-dns/compare/v1.3.0...v1.4.1)

---
updated-dependencies:
- dependency-name: async-dns
  dependency-type: direct:production
...

Signed-off-by: dependabot[bot] <support@github.com>

dyndnsd.gemspec

@@ -28,7 +28,7 @@ Gem::Specification.new do |s|
   s.required_ruby_version = '>= 3.0'
 
   s.add_dependency 'async', '~> 1.31.0'
-  s.add_dependency 'async-dns', '~> 1.3.0'
+  s.add_dependency 'async-dns', '>= 1.3', '< 1.5'
   s.add_dependency 'base64', '~> 0.2.0' # needed for async
   s.add_dependency 'logger', '~> 1.6.0'
   s.add_dependency 'metriks'