[cobal][protoc_wrapper] Explicitly use python3.11

Bug:b/298108341

Change-Id: If5cb3c66dc1433558d2d1542b79d139b8a481db4
diff --git a/protoc_wrapper.py b/protoc_wrapper.py
index 8dc4a44..c2baff4 100755
--- a/protoc_wrapper.py
+++ b/protoc_wrapper.py
@@ -1,4 +1,4 @@
-#!/usr/bin/env python3.8
+#!/usr/bin/env python3.11
 # Copyright 2012 Google Inc.  All Rights Reserved.
 
 """