Use COINBASE_MATURITY constant in functional tests.

test/functional/wallet_descriptor.py

@@ -4,6 +4,7 @@
 # file COPYING or http://www.opensource.org/licenses/mit-license.php.
 """Test descriptor wallet function."""
 
+from test_framework.blocktools import COINBASE_MATURITY
 from test_framework.test_framework import BitcoinTestFramework
 from test_framework.util import (
     assert_equal,
@@ -83,7 +84,7 @@ class WalletDescriptorTest(BitcoinTestFramework):
         send_wrpc = self.nodes[0].get_wallet_rpc("desc1")
 
         # Generate some coins
-        send_wrpc.generatetoaddress(101, send_wrpc.getnewaddress())
+        send_wrpc.generatetoaddress(COINBASE_MATURITY + 1, send_wrpc.getnewaddress())
 
         # Make transactions
         self.log.info("Test sending and receiving")