[FIX] website: restore button font-family in theme options

Since [1] when the layout of the theme options was reorganized, the
button's font-family option was not displayed anymore.

This commit restores the button's font-family inside the "Button"
section, before the button "Padding" options.

[1]: https://github.com/odoo/odoo/commit/388e4bb2bfcaebdd4ff30277fb49a034592d7086

task-3478355

closes odoo/odoo#140692

X-original-commit: 718ae15606fe452da26fe9c4fa9c90cc443fd8f1
Signed-off-by: Soukéina Bojabza (sobo) <sobo@odoo.com>
Signed-off-by: Benoit Socias (bso) <bso@odoo.com>

addons/website/static/src/scss/website.scss

@@ -136,6 +136,7 @@ $-seen-urls: ();
     @include print-variable('display-3-margin-bottom', $display-3-margin-bottom);
     @include print-variable('display-4-margin-bottom', $display-4-margin-bottom);
 
+    @include print-variable('set-buttons-font', o-get-font-info('buttons'));
     @include print-variable('btn-padding-y', $btn-padding-y);
     @include print-variable('btn-padding-x', $btn-padding-x);
     @include print-variable('btn-font-size', $btn-font-size);

addons/website/views/snippets/snippets.xml

@@ -1882,6 +1882,12 @@
         <we-input string="Border Width" class="o_we_sublevel_1" data-customize-website-variable=""
             data-variable="btn-secondary-outline-border-width" data-dependencies="btn_secondary_outline_opt"
             data-unit="px" data-save-unit="rem"/>
+        <we-row string="Font family">
+            <we-fontfamilypicker data-variable="buttons-font"/>
+            <we-button class="fa fa-fw fa-remove o_we_hover_danger o_we_link" title="Reset to Paragraph Font Family"
+                data-customize-website-variable="" data-variable="buttons-font"
+                data-remove-font="set-buttons-font" data-no-preview="true"/>
+        </we-row>
         <we-collapse>
             <we-row string="Padding">
                 <we-input title="Y" data-customize-website-variable="" data-variable="btn-padding-y" data-unit="px" data-save-unit="rem"/>