test: increment mocked time for migrating wallet backups

The wallet backups performed before migration use the time as part of
their filename. As the time is mocked, increment it between migration
attempts to prevent file name conflicts which is a problem on Windows.

Author: m3dwards

test/functional/wallet_migration.py

@@ -485,11 +485,16 @@ def test_encrypted(self):
 
         # Use self.migrate_and_get_rpc to test this error to get everything copied over to the master node
         assert_raises_rpc_error(-4, "Error: Wallet decryption failed, the wallet passphrase was not provided or was incorrect", self.migrate_and_get_rpc, "encrypted")
+
         # Use the RPC directly on the master node for the rest of these checks
+        self.master_node.bumpmocktime(1) # Prevents filename duplication on wallet backups which is a problem on Windows
         assert_raises_rpc_error(-4, "Error: Wallet decryption failed, the wallet passphrase was not provided or was incorrect", self.master_node.migratewallet, "encrypted", "badpass")
+
+        self.master_node.bumpmocktime(1) # Prevents filename duplication on wallet backups which is a problem on Windows
         assert_raises_rpc_error(-4, "The passphrase contains a null character", self.master_node.migratewallet, "encrypted", "pass\0with\0null")
 
         # Verify we can properly migrate the encrypted wallet
+        self.master_node.bumpmocktime(1) # Prevents filename duplication on wallet backups which is a problem on Windows
         self.master_node.migratewallet("encrypted", passphrase="pass")
         wallet = self.master_node.get_wallet_rpc("encrypted")