[FIX] website_forum: enlarge answer textarea

This commit permits to enlarge the answer textarea in the forum.

Steps to reproduce the "issue" resolved by this commit:
- Go to /forum
- Click on a thread
- Click on "Answer"

=> The textarea is too small to write a long answer.

task-2865782

closes odoo/odoo#118519

Signed-off-by: Thibault Delavallee (tde) <tde@openerp.com>

addons/website_forum/static/src/js/website_forum.js

@@ -134,7 +134,7 @@ publicWidget.registry.websiteForum = publicWidget.Widget.extend({
             toolbar.push(['history', ['undo', 'redo']]);
 
             var options = {
-                height: 200,
+                height: 350,
                 minHeight: 80,
                 toolbar: toolbar,
                 styleWithSpan: false,