Reset SIGCONT handler to isolate test behavior

Author: meshulam

Lib/test/test_pyrepl/test_unix_console.py

@@ -401,10 +401,11 @@ def test_restore_in_thread(self, _os_write):
         thread.start()
         thread.join()  # this should not raise
 
-    @unittest.skipIf(not hasattr(signal, "SIGCONT"), "needs signal.SIGCONT")
+    @unittest.skipUnless(hasattr(signal, "SIGCONT"), "needs signal.SIGCONT")
     def test_sigcont_is_armed_only_by_prepare(self, _os_write):
         # gh-161254: A console must install its SIGCONT handler only while it
         # owns the terminal, i.e. between prepare() and restore().
+        signal.signal(signal.SIGCONT, signal.SIG_DFL)
         console = UnixConsole(term="xterm")
         self.assertEqual(signal.getsignal(signal.SIGCONT), signal.SIG_DFL)
         console.prepare()
@@ -414,7 +415,7 @@ def test_sigcont_is_armed_only_by_prepare(self, _os_write):
         console.restore()
         self.assertEqual(signal.getsignal(signal.SIGCONT), signal.SIG_DFL)
 
-    @unittest.skipIf(not hasattr(signal, "SIGCONT"), "needs signal.SIGCONT")
+    @unittest.skipUnless(hasattr(signal, "SIGCONT"), "needs signal.SIGCONT")
     def test_restore_without_prepare(self, _os_write):
         # gh-161254
         console = UnixConsole(term="xterm")