[Bug #945063] Get file extension correct. (2.3 bugfix candidate)

Lib/cgitb.py

@@ -274,7 +274,7 @@ class Hook:
 
         if self.logdir is not None:
             import os, tempfile
-            suffix = ['.html', '.txt'][self.format=="html"]
+            suffix = ['.txt', '.html'][self.format=="html"]
             (fd, path) = tempfile.mkstemp(suffix=suffix, dir=self.logdir)
             try:
                 file = os.fdopen(fd, 'w')