Merge #20179: test: Fix intermittent issue in wallet_import_rescan

faab86f test: Fix intermittent issue in wallet_send (MarcoFalke)
faca373 test: Fix intermittent issue in wallet_import_rescan (MarcoFalke)

Pull request description:

  Fixes the issue

  ```
   node2 2020-10-16T14:26:28.699593Z (mocktime: 2020-10-16T16:26:46Z) [msghand] Timeout downloading block 1131f0318b913e078402524f1e63e53d52171844dd8246a03b970e540cb56924 from peer=0, disconnecting

ACKs for top commit:
  fjahr:
    utACK faab86f

Tree-SHA512: 739e8ad488c50e6beae676fb6cb021033cca6192da4acb4512c182bd8843f2f42a4a07474118285cb1d91798904433e4abb09476cc9ce115aae87ce64db69eaf

Author: MarcoFalke

test/functional/wallet_import_rescan.py

@@ -182,6 +182,7 @@ def run_test(self):
             self.nodes[0].generate(1)  # Generate one block for each send
             variant.confirmation_height = self.nodes[0].getblockcount()
             variant.timestamp = self.nodes[0].getblockheader(self.nodes[0].getbestblockhash())["time"]
+        self.sync_all() # Conclude sync before calling setmocktime to avoid timeouts
 
         # Generate a block further in the future (past the rescan window).
         assert_equal(self.nodes[0].getrawmempool(), [])

test/functional/wallet_send.py

@@ -316,6 +316,7 @@ def run_test(self):
         res = self.nodes[0].sendrawtransaction(hex)
         self.nodes[0].generate(1)
         assert_equal(self.nodes[0].gettransaction(txid)["confirmations"], 1)
+        self.sync_all()
 
         self.log.info("Lock unspents...")
         utxo1 = w0.listunspent()[0]