Merge bitcoin/bitcoin#27093: test: Fix intermittent sync issue in wallet_pruning

fa9ec7b test: Fix intermittent sync issue in wallet_pruning (MarcoFalke)

Pull request description:

  The `sync_fun=self.no_op` has no motivation or rationale, and seems to be causing issues.

  Fix that by removing it.

  Actually fixes bitcoin/bitcoin#27065, see bitcoin/bitcoin#27066 (comment)

ACKs for top commit:
  fanquake:
    ACK fa9ec7b

Tree-SHA512: 3c67da6705d6698fcabb29de169a2b4723f74705c979380d1fddce5fe9595b4595445fd7d9790a6b2a89f10ce8ec3c64ce45248f58fd920b72b7b6fba8afb09f

Author: fanquake

test/functional/wallet_pruning.py

@@ -123,7 +123,7 @@ def run_test(self):
 
         # A blk*.dat file is 128MB
         # Generate 250 light blocks
-        self.generate(self.nodes[0], 250, sync_fun=self.no_op)
+        self.generate(self.nodes[0], 250)
         # Generate 50MB worth of large blocks in the blk00000.dat file
         self.mine_large_blocks(self.nodes[0], 50)