Minor layout adjustments to --union-tech

sqlmap.conf

@@ -144,9 +144,9 @@ unionTest = False
 # Technique to test for UNION query SQL injection
 # The possible techniques are by NULL bruteforcing (bf) or by ORDER BY
 # clause (ob)
-# Valid: bf, ob
-# Default: bf
-uTech = bf
+# Valid: NULL, OrderBy
+# Default: NULL
+uTech = NULL
 
 # Use the UNION query (inband) SQL injection to retrieve the queries
 # output. No need to go blind.