Merge bitcoin/bitcoin#23307: test: Remove unused node from mining_prioritisetransaction

fa44b07 test: Remove unused node from mining_prioritisetransaction (MarcoFalke)

Pull request description:

  No need to make the test slower with an unused node

ACKs for top commit:
  0xB10C:
    Code Review ACK fa44b07
  practicalswift:
    cr ACK fa44b07
  brunoerg:
    tACK fa44b07

Tree-SHA512: fd49d3ac5ead3693e6d0df8000a4dca20521cdd7d9041a6de289a0fb48fb28f8d3e2c36c8e3510ad0da9cdb0abacbdda83edb86c9cb94a221c800ebdfe29021c

Author: fanquake

test/functional/mining_prioritisetransaction.py

@@ -13,7 +13,7 @@
 class PrioritiseTransactionTest(BitcoinTestFramework):
     def set_test_params(self):
         self.setup_clean_chain = True
-        self.num_nodes = 2
+        self.num_nodes = 1
         self.extra_args = [[
             "-printpriority=1",
             "-acceptnonstdtxn=1",