To cover REVOKE in syntax

Co-authored-by: Phil Wright <[email protected]>

Author: NataliaIvakina

modules/ROOT/pages/authentication-authorization/property-based-access-control.adoc

@@ -29,7 +29,9 @@ To specify the property/value conditions of the read privilege, you can use the
 
 [source, syntax, role="noheader"]
 ----
-GRANT|DENY [IMMUTABLE] READ|TRAVERSE|MATCH
+{GRANT | DENY | REVOKE [GRANT | DENY]}
+[IMMUTABLE]
+{MATCH	 | READ | TRAVERSE}	
   ON { HOME GRAPH | GRAPH[S] { * | name[, ...] } }
     [
       ELEMENT[S] { * | label-or-rel-type[, ...] }
@@ -44,7 +46,7 @@ GRANT|DENY [IMMUTABLE] READ|TRAVERSE|MATCH
 WHERE [NOT] var.property { { = | <> | > | >= | < | <= } value | IS NULL | IS NOT NULL | IN { "["[value[, ...]]"]" | listParam } } ) 
 }
 
-  TO role[, ...]
+ {TO | FROM} role[, ...] 
 ----