message: test: Default blockversion to 4 in feature_block
  There is one tests that checks version=1 blocks are rejected. For all
  other tests the version doesn't matter as long as it is large enough.
diff: @@ -1251,7 +1251,7 @@ class FullBlockTest(BitcoinTestFramework):
  blocks = []
  spend = out[32]
  for i in range(89, LARGE_REORG_SIZE + 89):
  - b = self.next_block(i, spend, version=4)
  + b = self.next_block(i, spend)
  tx = CTransaction()
  script_length = MAX_BLOCK_BASE_SIZE - len(b.serialize()) - 69
  script_output = CScript([b'\x00' * script_length])
  @@ -1270,18 +1270,18 @@ class FullBlockTest(BitcoinTestFramework):
  self.move_tip(88)
  blocks2 = []
  for i in range(89, LARGE_REORG_SIZE + 89):
  - blocks2.append(self.next_block("alt" + str(i), version=4))
  + blocks2.append(self.next_block("alt" + str(i)))
  self.send_blocks(blocks2, False, force_send=True)
  # extend alt chain to trigger re-org
  - block = self.next_block("alt" + str(chain1_tip + 1), version=4)
  + block = self.next_block("alt" + str(chain1_tip + 1))
  self.send_blocks([block], True, timeout=2440)
  # ... and re-org back to the first chain
  self.move_tip(chain1_tip)
  - block = self.next_block(chain1_tip + 1, version=4)
  + block = self.next_block(chain1_tip + 1)
  self.send_blocks([block], False, force_send=True)
  - block = self.next_block(chain1_tip + 2, version=4)
  + block = self.next_block(chain1_tip + 2)
  self.send_blocks([block], True, timeout=2440)
  self.log.info("Reject a block with an invalid block header version")
  @@ -1289,7 +1289,7 @@ class FullBlockTest(BitcoinTestFramework):
  self.send_blocks([b_v1], success=False, force_send=True, reject_reason='bad-version(0x00000001)', reconnect=True)
  self.move_tip(chain1_tip + 2)
  - b_cb34 = self.next_block('b_cb34', version=4)
  + b_cb34 = self.next_block('b_cb34')
  b_cb34.vtx[0].vin[0].scriptSig = b_cb34.vtx[0].vin[0].scriptSig[:-1]
  b_cb34.vtx[0].rehash()
  b_cb34.hashMerkleRoot = b_cb34.calc_merkle_root()
  @@ -1323,7 +1323,7 @@ class FullBlockTest(BitcoinTestFramework):
  tx.rehash()
  return tx
  - def next_block(self, number, spend=None, additional_coinbase_value=0, script=CScript([OP_TRUE]), *, version=1):
  + def next_block(self, number, spend=None, additional_coinbase_value=0, script=CScript([OP_TRUE]), *, version=4):
  if self.tip is None:
  base_block_hash = self.genesis_hash
  block_time = int(time.time()) + 1
  