Stop importing old style buttons

app/assets/stylesheets/app.scss

@@ -220,7 +220,3 @@ details .arrow {
 .heading-upcoming-jobs {
   margin-top: $gutter-half;
 }
-
-.button-secondary {
-  @include button($grey-3);
-}

app/assets/stylesheets/components/stick-at-top-when-scrolling.scss

@@ -60,10 +60,6 @@ $sticky-padding: $gutter * 2 / 3;
     margin: 0;
   }
 
-  .button-secondary {
-    margin: 0 $gutter-half 3px 0;
-  }
-
 }
 
 .content-fixed,

app/assets/stylesheets/globals.scss

@@ -80,15 +80,8 @@ a {
 
 input:focus,
 textarea:focus,
-select:focus,
-button:focus {
+select:focus
+{
   outline: 3px solid $focus-colour;
   outline-offset: 0;
 }
-
-// To be removed when all buttons follow the GOV.UK Frontend conventions
-// - https://design-system.service.gov.uk/components/button/
-
-button {
-  font-family: $govuk-font-family-nta;
-}

app/assets/stylesheets/main.scss

@@ -11,7 +11,6 @@ $path: '/static/images/';
 @import 'typography';
 @import 'grid_layout';
 @import 'helpers';
-@import 'design-patterns/buttons';
 
 // Dependencies from GOVU.UK Frontend Toolkit, rewritten for this application
 @import 'url-helpers';
@@ -23,7 +22,6 @@ $path: '/static/images/';
 // https://github.com/alphagov/govuk_elements
 @import 'elements/helpers';
 @import 'elements/reset';
-@import 'elements/buttons';
 @import 'elements/details';
 @import 'elements/elements-typography';
 @import 'elements/forms';