Remove -zapwallettxes

-zapwallettxes is made a hidden option to inform users that it is
removed and they should be using abandontransaction to do the stuck
transaction thing.

test/functional/wallet_basic.py

@@ -526,8 +526,6 @@ class WalletTest(BitcoinTestFramework):
         maintenance = [
             '-rescan',
             '-reindex',
-            '-zapwallettxes=1',
-            '-zapwallettxes=2',
         ]
         chainlimit = 6
         for m in maintenance: