Fix the range of existing userids in the loadtest.
Fix the range of existing userids in the loadtest.

shane-tomlinson/fxa-auth-server,dannycoates/picl-idp,eoger/fxa-auth-server,shane-tomlinson/fxa-auth-server,mozilla/fxa-auth-server,dannycoates/picl-idp,TDA/fxa-auth-server,dannycoates/picl-idp,mozilla/fxa-auth-server,TDA/fxa-auth-server,shane-tomlinson/fxa-auth-server,TDA/fxa-auth-server,mozilla/fxa-auth-server,eoger/fxa-auth-server,shane-tomlinson/fxa-auth-server,eoger/fxa-auth-server,dannycoates/picl-idp,eoger/fxa-auth-server,TDA/fxa-auth-server,mozilla/fxa-auth-server