[rubygems/rubygems] Allow bundler to load from the dependency api

https://github.com/rubygems/rubygems/commit/3303957286

lib/rubygems/safe_marshal.rb

@@ -1,5 +1,7 @@
 # frozen_string_literal: true
 
+require "stringio"
+
 require_relative "safe_marshal/reader"
 require_relative "safe_marshal/visitors/to_ruby"
 
@@ -31,6 +33,11 @@ module Gem
     PERMITTED_SYMBOLS = %w[
       development
       runtime
+
+      name
+      number
+      platform
+      dependencies
     ].freeze
     private_constant :PERMITTED_SYMBOLS
 

lib/rubygems/safe_marshal/visitors/to_ruby.rb

@@ -258,7 +258,7 @@ module Gem::SafeMarshal
       end
 
       COMPAT_CLASSES = {}.tap do |h|
-        h[Rational] = RationalCompat if RUBY_VERSION >= "3"
+        h[Rational] = RationalCompat
       end.freeze
       private_constant :COMPAT_CLASSES