Fix minor typo in rails/engine docs [ci skip]
Fix minor typo in rails/engine docs [ci skip]

schuetzm/rails,kddeisz/rails,fabianoleittes/rails,gauravtiwari/rails,yalab/rails,georgeclaghorn/rails,prathamesh-sonpatki/rails,bogdanvlviv/rails,jeremy/rails,vipulnsward/rails,yawboakye/rails,Vasfed/rails,esparta/rails,tgxworld/rails,lcreid/rails,Stellenticket/rails,BlakeWilliams/rails,BlakeWilliams/rails,mechanicles/rails,rails/rails,esparta/rails,fabianoleittes/rails,Edouard-chin/rails,mechanicles/rails,joonyou/rails,joonyou/rails,Erol/rails,tgxworld/rails,iainbeeston/rails,schuetzm/rails,fabianoleittes/rails,tjschuck/rails,jeremy/rails,EmmaB/rails-1,vipulnsward/rails,betesh/rails,MSP-Greg/rails,Stellenticket/rails,rails/rails,Stellenticket/rails,arunagw/rails,Erol/rails,Envek/rails,eileencodes/rails,BlakeWilliams/rails,notapatch/rails,palkan/rails,Envek/rails,bogdanvlviv/rails,MSP-Greg/rails,iainbeeston/rails,yhirano55/rails,jeremy/rails,esparta/rails,joonyou/rails,Stellenticket/rails,georgeclaghorn/rails,betesh/rails,georgeclaghorn/rails,iainbeeston/rails,tjschuck/rails,shioyama/rails,Erol/rails,prathamesh-sonpatki/rails,prathamesh-sonpatki/rails,notapatch/rails,palkan/rails,notapatch/rails,kmcphillips/rails,Vasfed/rails,lcreid/rails,shioyama/rails,kddeisz/rails,rafaelfranca/omg-rails,tgxworld/rails,eileencodes/rails,jeremy/rails,rails/rails,kmcphillips/rails,yawboakye/rails,EmmaB/rails-1,BlakeWilliams/rails,bogdanvlviv/rails,arunagw/rails,starknx/rails,arunagw/rails,georgeclaghorn/rails,iainbeeston/rails,betesh/rails,vipulnsward/rails,betesh/rails,starknx/rails,Envek/rails,yalab/rails,starknx/rails,Vasfed/rails,Vasfed/rails,yawboakye/rails,tgxworld/rails,MSP-Greg/rails,vipulnsward/rails,bogdanvlviv/rails,schuetzm/rails,Edouard-chin/rails,schuetzm/rails,yalab/rails,yhirano55/rails,kddeisz/rails,rafaelfranca/omg-rails,Edouard-chin/rails,lcreid/rails,eileencodes/rails,Erol/rails,yahonda/rails,tjschuck/rails,mechanicles/rails,repinel/rails,joonyou/rails,rails/rails,kddeisz/rails,fabianoleittes/rails,repinel/rails,gauravtiwari/rails,yahonda/rails,yahonda/rails,shioyama/rails,prathamesh-sonpatki/rails,tjschuck/rails,gauravtiwari/rails,mechanicles/rails,kmcphillips/rails,EmmaB/rails-1,arunagw/rails,rafaelfranca/omg-rails,notapatch/rails,yhirano55/rails,yalab/rails,kmcphillips/rails,Envek/rails,esparta/rails,Edouard-chin/rails,yahonda/rails,yhirano55/rails,yawboakye/rails,eileencodes/rails,lcreid/rails,palkan/rails,repinel/rails,shioyama/rails,repinel/rails,MSP-Greg/rails,palkan/rails