Fix tiny error in test_call_and_callcode_gas_calculation.

Author: evgenyzdanovich

tests/frontier/opcodes/test_call_and_callcode_gas_calculation.py

@@ -63,7 +63,7 @@
 
 
 @pytest.fixture
-def callee_code(callee_opcode: Op) -> Bytecode:
+def callee_code(pre: Alloc, callee_opcode: Op) -> Bytecode:
     """
     Code called by the caller contract:
         PUSH1 0x00 * 4
@@ -72,7 +72,9 @@ def callee_code(callee_opcode: Op) -> Bytecode:
         GAS <- value doesn't matter
         CALL/CALLCODE.
     """
-    return callee_opcode(Op.GAS(), 0xFEFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF, 1, 0, 0, 0, 0)
+    # The address needs to be empty and different for each execution of the fixture,
+    # otherwise the calculations (empty_account_cost) are incorrect.
+    return callee_opcode(Op.GAS(), pre.empty_account(), 1, 0, 0, 0, 0)
 
 
 @pytest.fixture