padrino アプリでactiverecordを5.1系から5.2.0に上げようとしたら rake ar:migrate でエラーになったので直した

エラー内容

activerecord 5.2系からは ActiveRecord::Migrator.migrate がなくなったとのこと。めちょっく！

$ bundle exec rake ar:migrate:reset --trace
** Invoke ar:migrate:reset (first_time)
** Invoke ar:drop (first_time)
** Invoke skeleton (first_time)
** Execute skeleton
** Execute ar:drop
** Invoke ar:create (first_time)
** Invoke skeleton
** Execute ar:create
** Invoke ar:migrate (first_time)
** Invoke skeleton
** Execute ar:migrate
rake aborted!
NoMethodError: undefined method `migrate' for ActiveRecord::Migrator:Class
/app/vendor/bundle/ruby/2.5.0/gems/padrino-gen-0.14.3/lib/padrino-gen/padrino-tasks/activerecord.rb:127:in `block (2 levels) in <top (required)>'
/app/vendor/bundle/ruby/2.5.0/gems/rake-12.3.1/lib/rake/task.rb:271:in `block in execute'
/app/vendor/bundle/ruby/2.5.0/gems/rake-12.3.1/lib/rake/task.rb:271:in `each'
/app/vendor/bundle/ruby/2.5.0/gems/rake-12.3.1/lib/rake/task.rb:271:in `execute'
/app/vendor/bundle/ruby/2.5.0/gems/rake-12.3.1/lib/rake/task.rb:213:in `block in invoke_with_call_chain'
/Users/sue445/.rbenv/versions/2.5.1/lib/ruby/2.5.0/monitor.rb:226:in `mon_synchronize'
/app/vendor/bundle/ruby/2.5.0/gems/rake-12.3.1/lib/rake/task.rb:193:in `invoke_with_call_chain'
/app/vendor/bundle/ruby/2.5.0/gems/rake-12.3.1/lib/rake/task.rb:237:in `block in invoke_prerequisites'
/app/vendor/bundle/ruby/2.5.0/gems/rake-12.3.1/lib/rake/task.rb:235:in `each'
/app/vendor/bundle/ruby/2.5.0/gems/rake-12.3.1/lib/rake/task.rb:235:in `invoke_prerequisites'
/app/vendor/bundle/ruby/2.5.0/gems/rake-12.3.1/lib/rake/task.rb:212:in `block in invoke_with_call_chain'
/Users/sue445/.rbenv/versions/2.5.1/lib/ruby/2.5.0/monitor.rb:226:in `mon_synchronize'
/app/vendor/bundle/ruby/2.5.0/gems/rake-12.3.1/lib/rake/task.rb:193:in `invoke_with_call_chain'
/app/vendor/bundle/ruby/2.5.0/gems/rake-12.3.1/lib/rake/task.rb:182:in `invoke'
/app/vendor/bundle/ruby/2.5.0/gems/rake-12.3.1/lib/rake/application.rb:160:in `invoke_task'
/app/vendor/bundle/ruby/2.5.0/gems/rake-12.3.1/lib/rake/application.rb:116:in `block (2 levels) in top_level'
/app/vendor/bundle/ruby/2.5.0/gems/rake-12.3.1/lib/rake/application.rb:116:in `each'
/app/vendor/bundle/ruby/2.5.0/gems/rake-12.3.1/lib/rake/application.rb:116:in `block in top_level'
/app/vendor/bundle/ruby/2.5.0/gems/rake-12.3.1/lib/rake/application.rb:125:in `run_with_threads'
/app/vendor/bundle/ruby/2.5.0/gems/rake-12.3.1/lib/rake/application.rb:110:in `top_level'
/app/vendor/bundle/ruby/2.5.0/gems/rake-12.3.1/lib/rake/application.rb:83:in `block in run'
/app/vendor/bundle/ruby/2.5.0/gems/rake-12.3.1/lib/rake/application.rb:186:in `standard_exception_handling'
/app/vendor/bundle/ruby/2.5.0/gems/rake-12.3.1/lib/rake/application.rb:80:in `run'
/app/vendor/bundle/ruby/2.5.0/gems/rake-12.3.1/exe/rake:27:in `<top (required)>'
/app/vendor/bundle/ruby/2.5.0/bin/rake:23:in `load'
/app/vendor/bundle/ruby/2.5.0/bin/rake:23:in `<top (required)>'
/Users/sue445/.rbenv/versions/2.5.1/lib/ruby/gems/2.5.0/gems/bundler-1.16.1/lib/bundler/cli/exec.rb:75:in `load'
/Users/sue445/.rbenv/versions/2.5.1/lib/ruby/gems/2.5.0/gems/bundler-1.16.1/lib/bundler/cli/exec.rb:75:in `kernel_load'
/Users/sue445/.rbenv/versions/2.5.1/lib/ruby/gems/2.5.0/gems/bundler-1.16.1/lib/bundler/cli/exec.rb:28:in `run'
/Users/sue445/.rbenv/versions/2.5.1/lib/ruby/gems/2.5.0/gems/bundler-1.16.1/lib/bundler/cli.rb:424:in `exec'
/Users/sue445/.rbenv/versions/2.5.1/lib/ruby/gems/2.5.0/gems/bundler-1.16.1/lib/bundler/vendor/thor/lib/thor/command.rb:27:in `run'
/Users/sue445/.rbenv/versions/2.5.1/lib/ruby/gems/2.5.0/gems/bundler-1.16.1/lib/bundler/vendor/thor/lib/thor/invocation.rb:126:in `invoke_command'
/Users/sue445/.rbenv/versions/2.5.1/lib/ruby/gems/2.5.0/gems/bundler-1.16.1/lib/bundler/vendor/thor/lib/thor.rb:387:in `dispatch'
/Users/sue445/.rbenv/versions/2.5.1/lib/ruby/gems/2.5.0/gems/bundler-1.16.1/lib/bundler/cli.rb:27:in `dispatch'
/Users/sue445/.rbenv/versions/2.5.1/lib/ruby/gems/2.5.0/gems/bundler-1.16.1/lib/bundler/vendor/thor/lib/thor/base.rb:466:in `start'
/Users/sue445/.rbenv/versions/2.5.1/lib/ruby/gems/2.5.0/gems/bundler-1.16.1/lib/bundler/cli.rb:18:in `start'
/Users/sue445/.rbenv/versions/2.5.1/lib/ruby/gems/2.5.0/gems/bundler-1.16.1/exe/bundle:30:in `block in <top (required)>'
/Users/sue445/.rbenv/versions/2.5.1/lib/ruby/gems/2.5.0/gems/bundler-1.16.1/lib/bundler/friendly_errors.rb:122:in `with_friendly_errors'
/Users/sue445/.rbenv/versions/2.5.1/lib/ruby/gems/2.5.0/gems/bundler-1.16.1/exe/bundle:22:in `<top (required)>'
/Users/sue445/.rbenv/versions/2.5.1/bin/bundle:23:in `load'
/Users/sue445/.rbenv/versions/2.5.1/bin/bundle:23:in `<main>'
Tasks: TOP => ar:migrate:reset => ar:migrate