[rubygems/rubygems] Remove unnecessary special case for Bundler

https://github.com/rubygems/rubygems/commit/2777e79b8e

lib/bundler/definition.rb

@@ -524,10 +524,8 @@ module Bundler
         end
       end
 
-      unless specs["bundler"].any?
-        bundler = sources.metadata_source.specs.search(Gem::Dependency.new("bundler", VERSION)).last
-        specs["bundler"] = bundler
-      end
+      bundler = sources.metadata_source.specs.search(Gem::Dependency.new("bundler", VERSION)).last
+      specs["bundler"] = bundler
 
       specs
     end

lib/bundler/spec_set.rb

@@ -35,10 +35,6 @@ module Bundler
         end
       end
 
-      if spec = lookup["bundler"].first
-        specs << spec
-      end
-
       specs
     end