pythonlib/script: return debug level also for the first invocation (inconsistent undocumented function return values inconsitency found by python -3 option used in tests - None > 0 is DeprecationWarning in 2.7, TypeError in 3.x)

git-svn-id: https://svn.osgeo.org/grass/grass/trunk@61272 15284696-431f-4ddb-bdfa-cd5b030d7da7

lib/python/script/core.py

@@ -1734,6 +1734,7 @@ def debug_level():
     _debug_level = 0
     if find_program('g.gisenv', '--help'):
         _debug_level = int(gisenv().get('DEBUG', 0))
+    return _debug_level
 
 
 def legal_name(s):