[CBR-12] appveyor: fix execution of wallet-new test suite
[CBR-12] appveyor: fix execution of wallet-new test suite

wallet-unit-tests was not running with
ExitFailure -1073741515 => 0xc0000135 => STATUS_DLL_NOT_FOUND

Solution: provide rocksdb.dll in wallet-new directory before testing
on windows.

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