[IMP] website: review bold style in Text Block snippet
[IMP] website: review bold style in Text Block snippet

Otherwise, when the user starts typing, this makes the text bold by
default.

Part of https://github.com/odoo/odoo/pull/46809
task-2182909
ygol/odoo,ygol/odoo,ygol/odoo,ygol/odoo,ygol/odoo,ygol/odoo,ygol/odoo