Merge #733: Fix assets_tutorial.py signblock dynafed error

f302515 Fix assets_tutorial.py signblock dynafed error (wintercooled)

Pull request description:

  Versions 0.18+ require a witnessScript argument for signblock unless the start arguments specify the ``con_dyna_deploy_start`` argument as ``0``.

Tree-SHA512: cb12eaf7664868ad741a72188db8e5c6337e9376b48972698eda7c333afbaf8f99b138aadba3b877977a2b34d0a32551c6c0606e1836af2c41939b227dd58647

contrib/assets_tutorial/assets_tutorial.py

@@ -312,7 +312,8 @@ def sync_all(e1, e2):
 signblockarg="-signblockscript=5221"+pubkey1+"21"+pubkey2+"52ae"
 # Anti-DoS argument, custom chain default is ~1 sig so let's make it at least 2 sigs
 blocksign_max_size="-con_max_block_sig_size=150"
-extra_args=signblockarg+" "+blocksign_max_size
+dyna_deploy_start="-con_dyna_deploy_start=0"
+extra_args=signblockarg+" "+blocksign_max_size+" "+dyna_deploy_start
 
 # Wipe out datadirs, start over
 shutil.rmtree(e1_datadir)