[FIX] website: resolving traceback Issue when creating Tasks/Tickets

Issue:
A traceback error was observed when attempting to create a task or ticket using
 the website form.

Cause:
This issue arise as a result of converting RPC  to ORM  readSearch. The problem
lay in the domain being passed to the ORM. Not all fields had a defined domain,
causing 'undefined' to be passed to the ORM, leading to the traceback error.

Fix:
To address this, we have introduced an 'or' condition within the domain. Now, if
a field has a domain, it will be passed accordingly; otherwise, an empty array
is set as the domain. This modification resolves the traceback issue.

Task-3526887

closes odoo/odoo#137359

Signed-off-by: Romain Derie (rde) <rde@odoo.com>

addons/website/static/src/snippets/s_website_form/options.js

@@ -71,7 +71,7 @@ const FormEditor = options.Class.extend({
                 display_name: el[1],
             }));
         } else if (field.relation && field.relation !== 'ir.attachment') {
-            field.records = await this.orm.searchRead(field.relation, field.domain, ["display_name"]);
+            field.records = await this.orm.searchRead(field.relation, field.domain || [], ["display_name"]);
         }
         return field.records;
     },