Fix 'process_result must fail' test missing expected_result

Without expected_result, a False process_result value does not fail the
test. Adding expected_result: True makes the comparison fail as intended.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

test/validation/items/common/results/test.tum

@@ -92,6 +92,7 @@
             func_name: echo
             param: [ $(str_example) ]
             process_result: "'44' in '$(result)'"
+            expected_result: True
         - py_func:
             name: Save the result in a global variable
             key: $(test)_PASS