Merge bitcoin/bitcoin#28108: test: fix intermittent failure in wallet_resendwallettransactions.py

e667bd68a1 test: fix intermittent failure in wallet_resendwallettransactions.py (Martin Zumsande)

Pull request description:

  Fixes #28094

  The test bumps the mocktime for ~2 weeks and then triggers eviction from the mempool. But this bump will also cause a new resubmit, and if the timing is such that this resubmit happens right after the eviction and before the check that the tx was evicted, the test can fail as in #28094:

  ```
  node0 2023-07-17T21:31:23.809483Z (mocktime: 2023-08-02T09:46:27Z) [httpworker.1] [validation.cpp:267] [LimitMempoolSize] [mempool] Expired 2 transactions from the memory pool
  node0 2023-07-17T21:31:23.810079Z (mocktime: 2023-08-02T09:46:27Z) [scheduler] [wallet/wallet.h:895] [WalletLogPrintf] [default wallet] ResubmitWalletTransactions: resubmit 2 unconfirmed transactions
  node0 2023-07-17T21:31:23.810474Z (mocktime: 2023-08-02T09:46:27Z) [httpworker.2] [rpc/request.cpp:181] [parse] [rpc] ThreadRPCServer method=getmempoolentry user=__cookie__
  2023-07-17T21:31:23.811000Z TestFramework (ERROR): Assertion failed (...) AssertionError: No exception raised
  ```
  Fix this by flushing out the current resubmit call before triggering mempool eviction.

ACKs for top commit:
  MarcoFalke:
    Nice. lgtm ACK e667bd68a1
  achow101:
    ACK e667bd68a1
  jonatack:
    Light "this looks like the other tests in this file" ACK e667bd68a1

Tree-SHA512: 027c2177ecd8bea80ec388ec2564f8fcbc717efd2722304b16fc0e9fa7ad216af61977c4e360b8135de68586cf13b0aa729ffa4fa27bad655092c3a55f73933c

test/functional/wallet_resendwallettransactions.py

@@ -108,9 +108,13 @@ class ResendWalletTransactionsTest(BitcoinTestFramework):
         # Set correct m_best_block_time, which is used in ResubmitWalletTransactions
         node.syncwithvalidationinterfacequeue()
 
-        # Evict these txs from the mempool
         evict_time = block_time + 60 * 60 * DEFAULT_MEMPOOL_EXPIRY_HOURS + 5
-        node.setmocktime(evict_time)
+        # Flush out currently scheduled resubmit attempt now so that there can't be one right between eviction and check.
+        with node.assert_debug_log(['resubmit 2 unconfirmed transactions']):
+            node.setmocktime(evict_time)
+            node.mockscheduler(60)
+
+        # Evict these txs from the mempool
         indep_send = node.send(outputs=[{node.getnewaddress(): 1}], inputs=[indep_utxo])
         node.getmempoolentry(indep_send["txid"])
         assert_raises_rpc_error(-5, "Transaction not in mempool", node.getmempoolentry, txid)