remove code that was previously unreachable

Some code that used to be unreachable was changed in https://github.com/bundler/bundler/issues/6829. This is causing some issues on some versions of Ruby, see #6849.

lib/bundler/source/metadata.rb

@@ -21,9 +21,8 @@ def specs
             # can't point to the actual gemspec or else the require paths will be wrong
             s.loaded_from = File.expand_path("..", __FILE__)
           end
-          if loaded_spec = Bundler.rubygems.loaded_specs("bundler")
-            idx << loaded_spec # this has to come after the fake gemspec, to override it
-          elsif local_spec = Bundler.rubygems.find_name("bundler").find {|s| s.version.to_s == VERSION }
+
+          if local_spec = Bundler.rubygems.find_name("bundler").find {|s| s.version.to_s == VERSION }
             idx << local_spec
           end