test: Remove unused wallet.dat

test/functional/data/wallets/high_minversion/GENERATE.md

@@ -1,8 +0,0 @@
-The wallet has been created by starting Bitcoin Core with the options
-`-regtest -datadir=/tmp -nowallet -walletdir=$(pwd)/test/functional/data/wallets/`.
-
-In the source code, `WalletFeature::FEATURE_LATEST` has been modified to be large, so that the minversion is too high
-for a current build of the wallet.
-
-The wallet has then been created with the RPC `createwallet high_minversion true true`, so that a blank wallet with
-private keys disabled is created.