Remove no longer necessary overrides

We were overriding these values because the `$body-font-family` and
`$global-radius` variables were defined after the values in the
`_settings.scss` file had been computed.

Now these values are defined before the values in the `_settings.scss`
are computed, so we don't need to override the values which depend on
them anymore.

app/assets/stylesheets/_consul_settings.scss

@@ -108,12 +108,8 @@ $white: #fdfdfd;
 
 $body-font-family: "Source Sans Pro", "Helvetica", "Arial", sans-serif !important;
 
-$header-font-family: $body-font-family;
-
 $global-radius: rem-calc(3);
 
-$button-radius: $global-radius;
-
 $header-styles: (
   small: (
     "h1": ("font-size": 34),
@@ -145,8 +141,6 @@ $tab-content-border: $border;
 
 $orbit-bullet-diameter: 0.8rem;
 
-$pagination-radius: $global-radius;
-
 $show-header-for-stacked: true;
 
 $tooltip-background-color: $brand;