test: create assert_not_equal util and add to where imports are needed

In the functional tests there are lots of cases where we assert != which
this new util will replace, we also are adding the imports and the new assertion

test/functional/wallet_descriptor.py

@@ -15,6 +15,7 @@ from test_framework.blocktools import COINBASE_MATURITY
 from test_framework.descriptors import descsum_create
 from test_framework.test_framework import BitcoinTestFramework
 from test_framework.util import (
+    assert_not_equal,
     assert_equal,
     assert_raises_rpc_error
 )
@@ -169,7 +170,7 @@ class WalletDescriptorTest(BitcoinTestFramework):
         with WalletUnlock(send_wrpc, "pass"):
             addr = send_wrpc.getnewaddress()
             info2 = send_wrpc.getaddressinfo(addr)
-            assert info1['hdmasterfingerprint'] != info2['hdmasterfingerprint']
+            assert_not_equal(info1['hdmasterfingerprint'], info2['hdmasterfingerprint'])
         assert 'hdmasterfingerprint' in send_wrpc.getaddressinfo(send_wrpc.getnewaddress())
         info3 = send_wrpc.getaddressinfo(addr)
         assert_equal(info2['desc'], info3['desc'])