scripted-diff: Use generate* from TestFramework

-BEGIN VERIFY SCRIPT-
 sed --regexp-extended -i \
     's/((self\.)?(nodes\[[^]]+\]|[a-z_]*(wallet|node)[0-9a-z_]*))\.(generate(|toaddress|block|todescriptor)(\(|, ))/self.\5\1, /g' \
     $(git grep -l generate ./test | grep -v 'test_framework/' | grep -v 'feature_rbf')
-END VERIFY SCRIPT-

test/functional/mempool_updatefromblock.py

@@ -91,7 +91,7 @@ class MempoolUpdateFromBlockTest(BitcoinTestFramework):
             if tx_count in n_tx_to_mine:
                 # The created transactions are mined into blocks by batches.
                 self.log.info('The batch of {} transactions has been accepted into the mempool.'.format(len(self.nodes[0].getrawmempool())))
-                block_hash = self.nodes[0].generate(1)[0]
+                block_hash = self.generate(self.nodes[0], 1)[0]
                 if not first_block_hash:
                     first_block_hash = block_hash
                 assert_equal(len(self.nodes[0].getrawmempool()), 0)