tests: remove python2 compatibility

tests/block_weight/block_weight.py

@@ -1,9 +1,8 @@
-#!/usr/bin/env python
+#!/usr/bin/env python3
 # Simulate a maximal block attack on the Monero network
 # This uses the scheme proposed by ArticMine
 # Written by Sarang Nother
 # Copyright (c) 2019-2024, The Monero Project
-from __future__ import print_function
 import sys
 import math
 

tests/block_weight/compare.py

@@ -1,6 +1,5 @@
-#!/usr/bin/env python
+#!/usr/bin/env python3
 
-from __future__ import print_function
 import sys
 import subprocess