[3.12] GH-94438: Fix RuntimeWarning for jump tests in test_sys_settrace (GH-111369)

(cherry picked from commit a254120)
Co-authored-by: Tian Gao <[email protected]>

Author: miss-islington

Lib/test/test_sys_settrace.py

@@ -9,6 +9,7 @@
 import asyncio
 from test.support import import_helper
 import contextlib
+import warnings
 
 support.requires_working_socket(module=True)
 
@@ -1970,6 +1971,9 @@ def run_test(self, func, jumpFrom, jumpTo, expected, error=None,
                 stack.enter_context(self.assertRaisesRegex(*error))
             if warning is not None:
                 stack.enter_context(self.assertWarnsRegex(*warning))
+            else:
+                stack.enter_context(warnings.catch_warnings())
+                warnings.simplefilter('error')
             func(output)
 
         sys.settrace(None)
@@ -2033,7 +2037,7 @@ def test_jump_simple_backwards(output):
         output.append(1)
         output.append(2)
 
-    @jump_test(1, 4, [5])
+    @jump_test(1, 4, [5], warning=(RuntimeWarning, unbound_locals))
     def test_jump_is_none_forwards(output):
         x = None
         if x is None:
@@ -2050,7 +2054,7 @@ def test_jump_is_none_backwards(output):
             output.append(5)
         output.append(6)
 
-    @jump_test(1, 4, [5])
+    @jump_test(2, 4, [5])
     def test_jump_is_not_none_forwards(output):
         x = None
         if x is not None: