Update ldap.md

doc/administration/auth/ldap.md

@@ -256,7 +256,7 @@ production:
 ```
 
 Tip: If you want to limit access to the nested members of an Active Directory
-group you can use the following syntax:
+group, you can use the following syntax:
 
 ```
 (memberOf:1.2.840.113556.1.4.1941:=CN=My Group,DC=Example,DC=com)