Merge bitcoin#30880: test: Wait for local services to update in feature_assumeutxo

19f4a7c test: Wait for local services to update in feature_assumeutxo (Fabian Jahr)

Pull request description:

  Closes bitcoin#30878

  It seems like there is a race where the block is stored locally and `getblock` does not error anymore, but `ActivateBestChain` has not finished yet, so the local services are not updated yet either. Fix this by waiting for the local services to update.

  Can be reproduced locally by adding the sleep here:

  ```cpp
  ──────────────────────────────────────────────────────────────────────────────────────────────────────────┐
  src/validation.cpp:3567: bool Chainstate::ActivateBestChain(BlockValidationState& state, std::shared_ptr< │
  ──────────────────────────────────────────────────────────────────────────────────────────────────────────┘
          }

          if (WITH_LOCK(::cs_main, return m_disabled)) {
              std::this_thread::sleep_for(std::chrono::seconds(10));
              // Background chainstate has reached the snapshot base block, so exit.

              // Restart indexes to resume indexing for all blocks unique to the snapshot
  ```

ACKs for top commit:
  maflcko:
    review-only ACK 19f4a7c
  achow101:
    ACK 19f4a7c
  pablomartin4btc:
    tACK 19f4a7c
  furszy:
    Code review ACK [19f4a7c](bitcoin@19f4a7c).

Tree-SHA512: 70dad3795988956c5e20f2d2d895fb56c5e3ce257c7547d3fd729c88949f0e24cb34594da1537bce8794ad02b2db44e7e46e995aa32539cd4dd84c4f1d4bb1c4

Author: achow101

test/functional/feature_assumeutxo.py

@@ -314,9 +314,9 @@ def test_sync_from_assumeutxo_node(self, snapshot):
         self.sync_blocks(nodes=(miner, snapshot_node))
         # Check the base snapshot block was stored and ensure node signals full-node service support
         self.wait_until(lambda: not try_rpc(-1, "Block not found", snapshot_node.getblock, snapshot_block_hash))
-        assert 'NETWORK' in snapshot_node.getnetworkinfo()['localservicesnames']
+        self.wait_until(lambda: 'NETWORK' in snapshot_node.getnetworkinfo()['localservicesnames'])
 
-        # Now the snapshot_node is sync, verify the ibd_node can sync from it
+        # Now that the snapshot_node is synced, verify the ibd_node can sync from it
         self.connect_nodes(snapshot_node.index, ibd_node.index)
         assert 'NETWORK' in ibd_node.getpeerinfo()[0]['servicesnames']
         self.sync_blocks(nodes=(ibd_node, snapshot_node))
@@ -698,7 +698,7 @@ def check_tx_counts(final: bool) -> None:
         self.wait_until(lambda: len(n2.getchainstates()['chainstates']) == 1)
 
         # Once background chain sync completes, the full node must start offering historical blocks again.
-        assert {'NETWORK', 'NETWORK_LIMITED'}.issubset(n2.getnetworkinfo()['localservicesnames'])
+        self.wait_until(lambda: {'NETWORK', 'NETWORK_LIMITED'}.issubset(n2.getnetworkinfo()['localservicesnames']))
 
         completed_idx_state = {
             'basic block filter index': COMPLETE_IDX,