testing / dev infrastructure fix for new mysql authentication settings
testing / dev infrastructure fix for new mysql authentication settings

Based on option 2 of the following stackoverflow answer:
https://stackoverflow.com/a/42742610

(And yes: The problem only occurred under standard ruby. Under jruby the
old way not only stayed working but the new way did not work!)

cargoserver/rubyrep,cargoserver/rubyrep,rubyrep/rubyrep,rubyrep/rubyrep