fix(config): improve sign-in confirmation email regex
fix(config): improve sign-in confirmation email regex

TDA/fxa-auth-server,eoger/fxa-auth-server,eoger/fxa-auth-server,shane-tomlinson/fxa-auth-server,mozilla/fxa-auth-server,shane-tomlinson/fxa-auth-server,eoger/fxa-auth-server,TDA/fxa-auth-server,TDA/fxa-auth-server,shane-tomlinson/fxa-auth-server,mozilla/fxa-auth-server,TDA/fxa-auth-server,eoger/fxa-auth-server,shane-tomlinson/fxa-auth-server,mozilla/fxa-auth-server,mozilla/fxa-auth-server