[FIX] sale: fix quantity non visible in portal

Create a sale order
Put an optional product with long description (no line break)
Save and confirm
Log in the portal with the receiving user, add the optional product to
the order.

The customer can't see the quantity of the optional product.
The number is not showing in the quantity adjustment widet.

opw-2304224

closes odoo/odoo#58226

X-original-commit: 27f6522f43c38d8eeed32285ce03fd1bb218aab2
Signed-off-by: agr-odoo <agr-odoo@users.noreply.github.com>

addons/sale/static/src/scss/sale_portal.scss

@@ -23,6 +23,7 @@
     .js_quantity {
         text-align: center;
         padding: 0;
+        min-width: 48px;
     }
 
     .input-group-text {
@@ -32,4 +33,4 @@
     @include media-breakpoint-down(sm) {
         width: 100%;
     }
-}
+}