[IMP] theme_*: explode masonry snippet

See community commit for details

Note: this also fixes avantgarde svg/screenshot at the same time: we
remove the s_masonry_block but add the missing carousel.

(image contribution by MANO)

closes odoo/design-themes#1020

Related: odoo/odoo#183755
Related: odoo/upgrade#6642
Signed-off-by: Quentin Smetz (qsm) <qsm@odoo.com>
Co-authored-by: mano-odoo <mano@odoo.com>

theme_aviato/static/src/js/tour.js

@@ -29,7 +29,7 @@ const snippets = [
         groupName: "Text",
     },
     {
-        id: 's_masonry_block',
+        id: 's_masonry_block_default_template',
         name: 'Masonry',
         groupName: "Images",
     },