[IMP] *: replace mobile menu feature by new mobile layout

See community commit for details.

task-3060986

Part-of: odoo/design-themes#651

theme_cobalt/models/theme_cobalt.py

@@ -7,4 +7,3 @@ class ThemeCobalt(models.AbstractModel):
     def _theme_cobalt_post_copy(self, mod):
         self.enable_asset("website.ripple_effect_scss")
         self.enable_asset("website.ripple_effect_js")
-        self.enable_header_off_canvas()

theme_cobalt/static/src/scss/primary_variables.scss

@@ -34,7 +34,6 @@ $o-website-values-palettes: (
 
         'headings-line-height': 1.1,
 
-        'hamburger-type': 'off-canvas',
         'menu-box-shadow': false,
 
         'btn-ripple': true,