Remove update-scenario.sh
Remove update-scenario.sh

This script was written by @volhovm and he allowed me to delete it, because
nobody uses it anymore.
We'll be able to restore it from git history if we need it later.
But note that it might be outdated.

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