fix typo

extension/Documentation/Manual.rst

@@ -7564,7 +7564,7 @@ DELETE - Delete
 Authorization
 -------------
 
-A QFQ form is only acessible via REST API, if ``Form.permitRest`` enables on of the HTTP Method: **get, post, put, delete**
+A QFQ form is only acessible via REST API, if ``Form.permitRest`` enables one of the HTTP Methods: **get, post, put, delete**
 
 ``Permit New`` or ``Permit Edit`` don't apply to QFQ forms called via REST.