[FIX] website: rte_translator ok in manual & debug

The rte_translator tour that test translation on the frontend could not
be started from the "[debug menu]" > "Start Tour" for two reasons:

- the start URL is not specified, so the test was started on current
backend page wich is wrong (in python the start url is "/")

- the backend original state (params after #) does not work with ?k=v
inside argument value, so `#return_url=/?debug=true`.

To solve this issue, we encode the return_url value and add a start url
when rte_translator is started manually.

opw-1998623
closes #33443

Signed-off-by: Nicolas Lempereur (nle) <nle@odoo.com>

addons/website/static/src/js/tours/rte.js

@@ -6,6 +6,7 @@ var base = require('web_editor.base');
 
 tour.register('rte_translator', {
     test: true,
+    url: '/',
     wait_for: base.ready(),
 }, [{
     content: "click on Add a language",

addons/website/views/website_templates.xml

@@ -401,7 +401,7 @@
             </div>
         </li>
         <li groups="website.group_website_publisher" class="list-inline-item">
-            <t t-set="url_return" t-value="url_for('', '[lang]') + '?' + keep_query()"/>
+            <t t-set="url_return" t-value="quote_plus(url_for('', '[lang]') + '?' + keep_query())"/>
             <a t-attf-href="/web#action=base.action_view_base_language_install&amp;website_id=#{website.id if website else ''}&amp;url_return=#{url_return}">
                 <i class="fa fa-plus-circle"/>
                 Add a language...