Merge prepare version of RubyGems 3.2.0

Merged: https://github.com/ruby/ruby/pull/3864

lib/rubygems/commands/specification_command.rb

@@ -126,6 +126,12 @@ Specific fields in the specification can be extracted in YAML format:
       terminate_interaction 1
     end
 
+    platform = get_platform_from_requirements(options)
+
+    if platform
+      specs = specs.select{|s| s.platform.to_s == platform }
+    end
+
     unless options[:all]
       specs = [specs.max_by {|s| s.version }]
     end