[REM] theme_*: remove useless scss variable overrides

This commit removes the overrides of scss variables that are set to the
default value and duplicated overrides.

task-2463604

closes odoo/design-themes#768

Signed-off-by: Outagant Mehdi (mou) <mou@odoo.com>

theme_vehicle/static/src/scss/primary_variables.scss

@@ -55,7 +55,6 @@ $o-theme-h2-font-size-multiplier: (38 / 16);
 $o-theme-h3-font-size-multiplier: (24 / 16);
 $o-theme-h4-font-size-multiplier: (20 / 16);
 $o-theme-h5-font-size-multiplier: (18 / 16);
-$o-theme-h6-font-size-multiplier: (16 / 16);
 
 $o-theme-headings-font-weight: 600;
 
@@ -110,7 +109,6 @@ $o-website-values-palettes: (
         'navbar-font': 'Fira Sans',
 
         'buttons-font': 'Fira Sans',
-        'btn-primary-outline': false,
         'btn-secondary-outline': true,
 
         'btn-border-width': 2px,
@@ -123,7 +121,6 @@ $o-website-values-palettes: (
         'btn-padding-y-lg': .6rem,
         'btn-font-size': 1.2rem,
 
-        'header-template': 'default',
         'header-links-style': 'border-bottom',
         'footer-template': 'minimalist',
     ),