envutil.rb: rename member
git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@39497 b2dd03c8-39d4-4d8f-98ff-823fe69b080e
envutil.rb: rename member
member to get rid of conflict with a method of Assertions.
git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@39497 b2dd03c8-39d4-4d8f-98ff-823fe69b080e