Use existing class in PersistenceTest::SaveTest
Use existing class in PersistenceTest::SaveTest

Creating a new class for widgets was causing failing tests because it
clashed with other widget classes. This test does not need to create its
own class, so I changed it to an existing class.

```
ARCONN=mysql2 bin/test --seed 25364 test/cases/*test.rb -n \
"/^(?:PrimaryKeyIntegerTest#(?:test_primary_key_with_serial_integer_are_automatically_numbered)|PersistenceTest::SaveTest#(?:test_save_touch_false))$/"
```

yawboakye/rails,tgxworld/rails,printercu/rails,repinel/rails,flanger001/rails,baerjam/rails,Envek/rails,notapatch/rails,utilum/rails,flanger001/rails,prathamesh-sonpatki/rails,bogdanvlviv/rails,joonyou/rails,betesh/rails,prathamesh-sonpatki/rails,vipulnsward/rails,tgxworld/rails,shioyama/rails,deraru/rails,untidy-hair/rails,kmayer/rails,shioyama/rails,mohitnatoo/rails,joonyou/rails,travisofthenorth/rails,pvalena/rails,alecspopa/rails,vipulnsward/rails,felipecvo/rails,gfvcastro/rails,deraru/rails,kmcphillips/rails,mathieujobin/reduced-rails-for-travis,fabianoleittes/rails,printercu/rails,yahonda/rails,odedniv/rails,pvalena/rails,georgeclaghorn/rails,baerjam/rails,gauravtiwari/rails,pvalena/rails,yawboakye/rails,gfvcastro/rails,kddeisz/rails,mechanicles/rails,EmmaB/rails-1,illacceptanything/illacceptanything,mathieujobin/reduced-rails-for-travis,aditya-kapoor/rails,bogdanvlviv/rails,yhirano55/rails,brchristian/rails,travisofthenorth/rails,yahonda/rails,EmmaB/rails-1,iainbeeston/rails,gcourtemanche/rails,assain/rails,shioyama/rails,rails/rails,printercu/rails,Stellenticket/rails,rafaelfranca/omg-rails,rails/rails,illacceptanything/illacceptanything,iainbeeston/rails,rails/rails,arunagw/rails,Vasfed/rails,notapatch/rails,MSP-Greg/rails,yasslab/railsguides.jp,Envek/rails,odedniv/rails,gfvcastro/rails,yalab/rails,prathamesh-sonpatki/rails,Edouard-chin/rails,iainbeeston/rails,yahonda/rails,aditya-kapoor/rails,illacceptanything/illacceptanything,deraru/rails,illacceptanything/illacceptanything,untidy-hair/rails,kamipo/rails,repinel/rails,mechanicles/rails,notapatch/rails,tgxworld/rails,tgxworld/rails,yasslab/railsguides.jp,BlakeWilliams/rails,alecspopa/rails,schuetzm/rails,illacceptanything/illacceptanything,lcreid/rails,yalab/rails,assain/rails,utilum/rails,vipulnsward/rails,MSP-Greg/rails,flanger001/rails,kamipo/rails,odedniv/rails,fabianoleittes/rails,illacceptanything/illacceptanything,illacceptanything/illacceptanything,kamipo/rails,Erol/rails,jeremy/rails,lcreid/rails,mohitnatoo/rails,palkan/rails,Stellenticket/rails,kmayer/rails,esparta/rails,georgeclaghorn/rails,Vasfed/rails,illacceptanything/illacceptanything,Envek/rails,jeremy/rails,betesh/rails,untidy-hair/rails,jeremy/rails,bogdanvlviv/rails,schuetzm/rails,MSP-Greg/rails,Vasfed/rails,Edouard-chin/rails,kaspth/rails,illacceptanything/illacceptanything,Stellenticket/rails,starknx/rails,notapatch/rails,rafaelfranca/omg-rails,georgeclaghorn/rails,Erol/rails,BlakeWilliams/rails,mohitnatoo/rails,kaspth/rails,gauravtiwari/rails,schuetzm/rails,Edouard-chin/rails,eileencodes/rails,repinel/rails,gauravtiwari/rails,illacceptanything/illacceptanything,lcreid/rails,kaspth/rails,yhirano55/rails,assain/rails,kirs/rails-1,gfvcastro/rails,BlakeWilliams/rails,ledestin/rails,deraru/rails,ledestin/rails,kddeisz/rails,yhirano55/rails,yasslab/railsguides.jp,palkan/rails,joonyou/rails,prathamesh-sonpatki/rails,EmmaB/rails-1,yawboakye/rails,brchristian/rails,felipecvo/rails,felipecvo/rails,starknx/rails,baerjam/rails,kmcphillips/rails,iainbeeston/rails,kddeisz/rails,joonyou/rails,gcourtemanche/rails,illacceptanything/illacceptanything,kmayer/rails,lcreid/rails,kddeisz/rails,palkan/rails,printercu/rails,esparta/rails,baerjam/rails,Vasfed/rails,georgeclaghorn/rails,shioyama/rails,yahonda/rails,MSP-Greg/rails,aditya-kapoor/rails,tjschuck/rails,flanger001/rails,travisofthenorth/rails,rails/rails,Envek/rails,illacceptanything/illacceptanything,alecspopa/rails,bogdanvlviv/rails,mechanicles/rails,vipulnsward/rails,esparta/rails,tjschuck/rails,mohitnatoo/rails,betesh/rails,gcourtemanche/rails,palkan/rails,ledestin/rails,mathieujobin/reduced-rails-for-travis,brchristian/rails,kmcphillips/rails,yhirano55/rails,arunagw/rails,Stellenticket/rails,eileencodes/rails,schuetzm/rails,yasslab/railsguides.jp,mechanicles/rails,yawboakye/rails,illacceptanything/illacceptanything,repinel/rails,illacceptanything/illacceptanything,utilum/rails,travisofthenorth/rails,eileencodes/rails,Sen-Zhang/rails,yalab/rails,arunagw/rails,kmcphillips/rails,starknx/rails,arunagw/rails,aditya-kapoor/rails,Edouard-chin/rails,illacceptanything/illacceptanything,yalab/rails,betesh/rails,kirs/rails-1,utilum/rails,eileencodes/rails,tjschuck/rails,kirs/rails-1,Sen-Zhang/rails,assain/rails,fabianoleittes/rails,fabianoleittes/rails,BlakeWilliams/rails,pvalena/rails,jeremy/rails,untidy-hair/rails,Sen-Zhang/rails,tjschuck/rails,Erol/rails,esparta/rails,Erol/rails,rafaelfranca/omg-rails