Switch to python 3

The python scripts in this repo supports both python2 and python3.
Use python3 now since python2 is EOL.

Signed-off-by: Jayanth Othayoth <ojayanth@in.ibm.com>
Change-Id: Ibcb2f2fdcdfbfa51a081586d34314afcba41ba87
diff --git a/errors_map_gen.py b/errors_map_gen.py
index 6e60610..47f05c6 100755
--- a/errors_map_gen.py
+++ b/errors_map_gen.py
@@ -1,4 +1,4 @@
-#!/usr/bin/env python
+#!/usr/bin/env python3
 
 import os
 import yaml
@@ -28,4 +28,4 @@
 
 if __name__ == '__main__':
     script_dir = os.path.dirname(os.path.realpath(__file__))
-    main()
\ No newline at end of file
+    main()