Reset error file handle

Author: kastiglione

lldb/test/API/commands/command/script/exception/TestCommandException.py

@@ -19,6 +19,7 @@ def test(self):
             self.dbg.SetErrorFileHandle(devnull, False)
             result = lldb.SBCommandReturnObject()
             self.ci.HandleCommand("throw", result)
+            self.dbg.SetErrorFileHandle(None, False)
 
         self.assertEqual(
             result.GetStatus(),