scripted-diff: test: Remove brackets after assert

-BEGIN VERIFY SCRIPT-
sed -i --regexp-extended -e 's/assert ?\((.+)\)(( )*)?(#.*)?$/assert \1\3\3\4/g' $(git grep -l --extended-regexp 'assert ?\(' test)
-END VERIFY SCRIPT-

test/functional/rpc_blockchain.py

@@ -172,9 +172,9 @@ class BlockchainTest(BitcoinTestFramework):
         assert_equal(chaintxstats['txcount'], 2)
         assert_equal(chaintxstats['window_final_block_hash'], b1_hash)
         assert_equal(chaintxstats['window_block_count'], 0)
-        assert('window_tx_count' not in chaintxstats)
-        assert('window_interval' not in chaintxstats)
-        assert('txrate' not in chaintxstats)
+        assert 'window_tx_count' not in chaintxstats
+        assert 'window_interval' not in chaintxstats
+        assert 'txrate' not in chaintxstats
 
     def _test_gettxoutsetinfo(self):
         node = self.nodes[0]