tests: Add missing sync_all to wallet_importdescriptors.py
tests: Add missing sync_all to wallet_importdescriptors.py

node1 will sometimes do sendtoaddress before it has received a funding
transaction which will cause the test to fail. sync_all to ensure it
gets the transaction first.


Former-commit-id: 99fdbe4b535d3c4891de9d5bb334fe653275bd1a
syscoin/syscoin,syscoin/syscoin,syscoin/syscoin,syscoin/syscoin,syscoin/syscoin,syscoin/syscoin,syscoin/syscoin,syscoin/syscoin