fix order dependent test in AggregationsTest
fix order dependent test in AggregationsTest

Ensure class variable is set to nil.

It prevents the following test to fail:

    def test_do_not_run_the_converter_when_nil_was_set
      customers(:david).non_blank_gps_location = nil
      assert_nil Customer.gps_conversion_was_run
    end

Check https://github.com/rails/rails/blob/master/activerecord/test/models/customer.rb#L7
for more information.

yalab/rails,BlakeWilliams/rails,notapatch/rails,MSP-Greg/rails,lucasmazza/rails,utilum/rails,yawboakye/rails,utilum/rails,kmcphillips/rails,Spin42/rails,kenta-s/rails,iainbeeston/rails,Vasfed/rails,deraru/rails,pvalena/rails,kenta-s/rails,alecspopa/rails,travisofthenorth/rails,baerjam/rails,mtsmfm/rails,gfvcastro/rails,gauravtiwari/rails,Edouard-chin/rails,yhirano55/rails,fabianoleittes/rails,vassilevsky/rails,assain/rails,pschambacher/rails,palkan/rails,georgeclaghorn/rails,kachick/rails,mathieujobin/reduced-rails-for-travis,betesh/rails,gcourtemanche/rails,mechanicles/rails,shioyama/rails,repinel/rails,repinel/rails,lcreid/rails,fabianoleittes/rails,mechanicles/rails,Vasfed/rails,bogdanvlviv/rails,pvalena/rails,jeremy/rails,rbhitchcock/rails,joonyou/rails,kirs/rails-1,illacceptanything/illacceptanything,Sen-Zhang/rails,kmcphillips/rails,yasslab/railsguides.jp,gfvcastro/rails,assain/rails,gavingmiller/rails,iainbeeston/rails,printercu/rails,MichaelSp/rails,untidy-hair/rails,coreyward/rails,BlakeWilliams/rails,prathamesh-sonpatki/rails,xlymian/rails,Envek/rails,georgeclaghorn/rails,88rabbit/newRails,fabianoleittes/rails,mtsmfm/rails,Stellenticket/rails,gauravtiwari/rails,sealocal/rails,samphilipd/rails,ngpestelos/rails,tjschuck/rails,matrinox/rails,esparta/rails,MSP-Greg/rails,mohitnatoo/rails,Spin42/rails,mohitnatoo/rails,voray/rails,amoody2108/TechForJustice,Erol/rails,odedniv/rails,illacceptanything/illacceptanything,bogdanvlviv/rails,utilum/rails,flanger001/rails,riseshia/railsguides.kr,bradleypriest/rails,BlakeWilliams/rails,tgxworld/rails,ledestin/rails,travisofthenorth/rails,ttanimichi/rails,koic/rails,kmayer/rails,arunagw/rails,pvalena/rails,matrinox/rails,xlymian/rails,Sen-Zhang/rails,sergey-alekseev/rails,gavingmiller/rails,kirs/rails-1,tijwelch/rails,vassilevsky/rails,88rabbit/newRails,yhirano55/rails,mtsmfm/railstest,kaspth/rails,betesh/rails,Erol/rails,marklocklear/rails,palkan/rails,ngpestelos/rails,prathamesh-sonpatki/rails,yahonda/rails,kaspth/rails,shioyama/rails,deraru/rails,kmcphillips/rails,sealocal/rails,yasslab/railsguides.jp,mathieujobin/reduced-rails-for-travis,marklocklear/rails,bogdanvlviv/rails,yasslab/railsguides.jp,yalab/rails,Vasfed/rails,rails/rails,hanystudy/rails,illacceptanything/illacceptanything,stefanmb/rails,Envek/rails,coreyward/rails,tjschuck/rails,kddeisz/rails,yawboakye/rails,kamipo/rails,Envek/rails,flanger001/rails,illacceptanything/illacceptanything,ngpestelos/rails,repinel/rails,schuetzm/rails,elfassy/rails,mtsmfm/rails,ttanimichi/rails,alecspopa/rails,rossta/rails,baerjam/rails,illacceptanything/illacceptanything,riseshia/railsguides.kr,deraru/rails,printercu/rails,esparta/rails,georgeclaghorn/rails,baerjam/rails,hanystudy/rails,vipulnsward/rails,fabianoleittes/rails,untidy-hair/rails,rails/rails,prathamesh-sonpatki/rails,bolek/rails,arunagw/rails,repinel/rails,tjschuck/rails,arjes/rails,Sen-Zhang/rails,voray/rails,aditya-kapoor/rails,vipulnsward/rails,elfassy/rails,xlymian/rails,lcreid/rails,MSP-Greg/rails,kmayer/rails,tjschuck/rails,mijoharas/rails,schuetzm/rails,lcreid/rails,mijoharas/rails,aditya-kapoor/rails,Envek/rails,kachick/rails,shioyama/rails,bradleypriest/rails,koic/rails,joonyou/rails,pschambacher/rails,esparta/rails,kamipo/rails,rails/rails,ledestin/rails,maicher/rails,sealocal/rails,mohitnatoo/rails,esparta/rails,assain/rails,matrinox/rails,Stellenticket/rails,coreyward/rails,eileencodes/rails,BlakeWilliams/rails,yahonda/rails,lucasmazza/rails,vipulnsward/rails,untidy-hair/rails,riseshia/railsguides.kr,palkan/rails,illacceptanything/illacceptanything,voray/rails,mathieujobin/reduced-rails-for-travis,sergey-alekseev/rails,deraru/rails,EmmaB/rails-1,kmayer/rails,marklocklear/rails,shioyama/rails,bogdanvlviv/rails,bradleypriest/rails,brchristian/rails,yhirano55/rails,illacceptanything/illacceptanything,Stellenticket/rails,maicher/rails,vipulnsward/rails,pschambacher/rails,elfassy/rails,Erol/rails,aditya-kapoor/rails,tijwelch/rails,brchristian/rails,kirs/rails-1,Vasfed/rails,jeremy/rails,bolek/rails,joonyou/rails,prathamesh-sonpatki/rails,arunagw/rails,koic/rails,jeremy/rails,Edouard-chin/rails,Stellenticket/rails,rbhitchcock/rails,betesh/rails,kddeisz/rails,felipecvo/rails,alecspopa/rails,flanger001/rails,travisofthenorth/rails,richseviora/rails,starknx/rails,palkan/rails,iainbeeston/rails,illacceptanything/illacceptanything,tgxworld/rails,bolek/rails,EmmaB/rails-1,felipecvo/rails,Spin42/rails,baerjam/rails,illacceptanything/illacceptanything,odedniv/rails,schuetzm/rails,amoody2108/TechForJustice,kddeisz/rails,betesh/rails,printercu/rails,starknx/rails,illacceptanything/illacceptanything,rafaelfranca/omg-rails,utilum/rails,stefanmb/rails,illacceptanything/illacceptanything,eileencodes/rails,richseviora/rails,joonyou/rails,gfvcastro/rails,rails/rails,mohitnatoo/rails,yhirano55/rails,iainbeeston/rails,assain/rails,samphilipd/rails,kaspth/rails,MSP-Greg/rails,yahonda/rails,tijwelch/rails,Edouard-chin/rails,arjes/rails,samphilipd/rails,yalab/rails,rosst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