allow JRuby to fail on Rails 5
allow JRuby to fail on Rails 5

the previous commit tried using the ActiveRecord adapter gem from
Github / master as mentioned here:
https://github.com/jruby/activerecord-jdbc-adapter/issues/700, but that
didn’t seem to have worked

deivid-rodriguez/activeadmin,mateusg/active_admin,waymondo/active_admin,chdem/activeadmin,gogovan/activeadmin,iuriandreazza/activeadmin,wspurgin/activeadmin,iuriandreazza/activeadmin,iuriandreazza/activeadmin,senid231/activeadmin,halilim/activeadmin,mauriciopasquier/active_admin,gogovan/activeadmin,senid231/activeadmin,whatcould/active_admin,SoftSwiss/active_admin,Ibotta/activeadmin,mateusg/active_admin,halilim/activeadmin,varyonic/activeadmin,varyonic/activeadmin,halilim/activeadmin,vytenis-s/activeadmin,vraravam/activeadmin,bolshakov/activeadmin,cmunozgar/activeadmin,siutin/activeadmin,quikly/active_admin,mrjman/activeadmin,Ibotta/activeadmin,siutin/activeadmin,vraravam/activeadmin,mrjman/activeadmin,javierjulio/activeadmin,chdem/activeadmin,deivid-rodriguez/activeadmin,quikly/active_admin,iuriandreazza/activeadmin,wspurgin/activeadmin,maysam/activeadmin,javierjulio/activeadmin,maysam/activeadmin,siutin/activeadmin,wspurgin/activeadmin,activeadmin/activeadmin,cmunozgar/activeadmin,mauriciopasquier/active_admin,gogovan/activeadmin,bolshakov/activeadmin,mateusg/active_admin,Ibotta/activeadmin,maysam/activeadmin,senid231/activeadmin,SoftSwiss/active_admin,iuriandreazza/activeadmin,vytenis-s/activeadmin,vytenis-s/activeadmin,vraravam/activeadmin,chdem/activeadmin,whatcould/active_admin,waymondo/active_admin,quikly/active_admin,mauriciopasquier/active_admin,mrjman/activeadmin,varyonic/activeadmin,SoftSwiss/active_admin,whatcould/active_admin,activeadmin/activeadmin,deivid-rodriguez/activeadmin,iuriandreazza/activeadmin,javierjulio/activeadmin,waymondo/active_admin,bolshakov/activeadmin,iuriandreazza/activeadmin,cmunozgar/activeadmin,activeadmin/activeadmin