[FIX] website: not fail when sharing page with an SEO title

Since [1] when the social share widget was introduced, a hashtag is
generated from the name of the website that is found inside the page
title.
This fails when the page title is replaced through the SEO feature.

This commit prevents the failure but not extracting the website name if
it is missing from the title.

Note that the `registry.socialShare` fixed here is only used by the
forum post page in the whole codebase. It is different from the social
snippet. The social snippet is doing the same code (kind of duplicate),
but it does not care about removing the | right part. It means that if
you drag & drop the "Share" snippet in a forum post page (like in the
footer) and click on it, it will work since it does not try to split on
the title's pipe.
In master, we will evaluate if we should remove this
`registry.socialShare` and use the `Share` snippet instead.

Steps to reproduce:
- Install website_forum.
- Go to a forum post.
- Set SEO title to a value without `|` (pipe).
- Share to X.

=> An error popup was shown.

[1]: https://github.com/odoo/odoo/commit/1c91e27c8c8cb7492d26f03e27c4991b53a1675d

opw-3799914

closes odoo/odoo#158478

X-original-commit: f89f4a8f1ad0ee3fb62ba246ea17988955dbdc4b
Signed-off-by: Romain Derie (rde) <rde@odoo.com>
Signed-off-by: Benoit Socias (bso) <bso@odoo.com>

addons/website/static/src/js/content/snippets.animation.js

@@ -971,8 +971,11 @@ registry.socialShare = publicWidget.Widget.extend({
     _renderSocial: function (social) {
         var url = this.$el.data('urlshare') || document.URL.split(/[?#]/)[0];
         url = encodeURIComponent(url);
-        var title = document.title.split(" | ")[0];  // get the page title without the company name
-        var hashtags = ' #' + document.title.split(" | ")[1].replace(' ', '') + ' ' + this.hashtags;  // company name without spaces (for hashtag)
+        const titleParts = document.title.split(" | ");
+        const title = titleParts[0]; // Get the page title without the company name
+        const hashtags = titleParts.length === 1
+            ? ` ${this.hashtags}`
+            : ` #${titleParts[1].replace(" ", "")} ${this.hashtags}`; // Company name without spaces (for hashtag)
         var socialNetworks = {
             'facebook': 'https://www.facebook.com/sharer/sharer.php?u=' + url,
             'twitter': 'https://twitter.com/intent/tweet?original_referer=' + url + '&text=' + encodeURIComponent(title + hashtags + ' - ') + url,