Updated part-1.md to match current AWS UI.
Updated part-1.md to match current AWS UI.

Also clarified where to obtain the Resource ARN for step 2.
Annyv2/docs,Catografix/docs,sandrinodimattia/docs,hamzawi06/docs,jeffreylees/docs,sandrinodimattia/docs,jeffreylees/docs,yvonnewilson/docs,Catografix/docs,hamzawi06/docs,jeffreylees/docs,yvonnewilson/docs,auth0/docs,khorne3/docs,yvonnewilson/docs,Annyv2/docs,hamzawi06/docs,sandrinodimattia/docs,auth0/docs,Annyv2/docs,khorne3/docs,Catografix/docs,khorne3/docs,auth0/docs