Fix use template buttons for creating a new project

app/assets/stylesheets/bootstrap_migration.scss

@@ -293,3 +293,7 @@ input[type=color].form-control {
     color: $gl-text-color-secondary;
   }
 }
+
+.btn {
+  margin-bottom: 0;
+}

app/views/projects/_project_templates.html.haml

@@ -10,7 +10,8 @@
       %a.btn.btn-default{ href: template.preview, rel: 'noopener noreferrer', target: '_blank' } Preview
 
   .project-fields-form
-    .form-group
+    .row
+      .form-group.col-sm-12
         %label.label-light
           Template
         .input-group.template-input-group