Revert replacement of 'tempfile.mktemp'.

Windows doesn't allow proper function with NamedTemporaryFile held open.

src/ZODB/tests/testConfig.py

@@ -61,7 +61,7 @@ class ZODBConfigTest(ConfigTestBase):
             """)
 
     def test_file_config1(self):
-        with tempfile.NamedTemporaryFile(prefix='Cfg') as f:
+        path = tempfile.mktemp()
         self._test(
             """
             <zodb>
@@ -69,10 +69,10 @@ class ZODBConfigTest(ConfigTestBase):
                 path %s
               </filestorage>
             </zodb>
-                """ % f.name)
+            """ % path)
 
     def test_file_config2(self):
-        with tempfile.NamedTemporaryFile(prefix='Cfg') as f:
+        path = tempfile.mktemp()
         cfg = """
         <zodb>
           <filestorage>
@@ -81,7 +81,7 @@ class ZODBConfigTest(ConfigTestBase):
             read-only true
           </filestorage>
         </zodb>
-            """ % f.name
+        """ % path
         self.assertRaises(ReadOnlyError, self._test, cfg)
 
     def test_demo_config(self):