[DEVOPS-1203] configuration.yaml: Testnet applicationVersion 7 -> 8
[DEVOPS-1203] configuration.yaml: Testnet applicationVersion 7 -> 8

This is for the next update proposal on testnet.

input-output-hk/cardano-sl,input-output-hk/cardano-sl,input-output-hk/cardano-sl,input-output-hk/pos-haskell-prototype,input-output-hk/pos-haskell-prototype,input-output-hk/cardano-sl,input-output-hk/pos-haskell-prototype