Fix paintIt method in JavaScript guides [ci skip]
Fix paintIt method in JavaScript guides [ci skip]

- Changed "paintIt" to "@paintIt" so that it can be called in an on
  click handler.
- Closes #22568

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