[FIX] website_blog: fix cover display on posts list page

This commit fixes a bug happening when changing the background with the
CoverProperties SnippetOption from the blog posts list page.
As it selects the default sizing class and applies it, the min-height
css property was applied and breaking the layout.

The covers min-height is now set as !important to not be overriden in
that context.

Part of https://github.com/odoo/odoo/pull/71593
task-2497846

X-original-commit: aa9591bf546729162f44d1f34cbee094131aba73

addons/website_blog/static/src/scss/website_blog.scss

@@ -248,6 +248,9 @@ $o-wblog-loader-size: 50px;
 
             padding-top: 33%;
             height: auto!important;
+            // This is mandatory as we do not want the CoverProperties 
+            // sizing classes to be applied here
+            min-height: auto!important;
 
             &:hover .o_record_cover_image {
                 opacity: 0.8;