Work around warning about unused block argument

It'll be fixed in 3.4.2 https://bugs.ruby-lang.org/issues/21003

Author: flash-gordon

lib/dry/validation/macros.rb

@@ -80,8 +80,8 @@ def self.[](name)
       # @return [Macros]
       #
       # @api public
-      def self.register(name, ...)
-        container.register(name, ...)
+      def self.register(...)
+        container.register(...)
         self
       end