UX improvement for enabling payment provider plugins (#6364)

Make flow of enabling new payment plugin smoother by redirecting back to
payment settings, and highlighting the newly enabled provider.

src/pretix/control/templates/pretixcontrol/event/payment.html

@@ -12,7 +12,7 @@
                 <table class="table table-payment-providers">
                     <tbody>
                     {% for provider in providers %}
-                        <tr>
+                        <tr{% if provider.highlight %} class="success-left"{% endif %}>
                             <td>
                                 <strong>{{ provider.verbose_name }}</strong>
                             </td>
@@ -56,7 +56,7 @@
                             <td colspan="4">
                                 <br>
                                 {% url "control:event.settings.plugins" event=request.event.slug organizer=request.organizer.slug as plugin_settings_url %}
-                                <a href="{{ plugin_settings_url }}#tab-0-1-open" class="btn btn-default">
+                                <a href="{{ plugin_settings_url }}?go=payment#tab-0-1-open" class="btn btn-default">
                                     <i class="fa fa-plus"></i> {% trans "Enable additional payment plugins" %}
                                 </a>
                             </td>

src/pretix/control/templates/pretixcontrol/event/plugins.html

@@ -28,6 +28,7 @@
     </div>
     <form action="" method="post" class="form-horizontal form-plugins">
         {% csrf_token %}
+        <input type="hidden" name="go" value="{{ request.GET.go }}">
         <div id="plugin_search_results" class="panel panel-default collapse">
             <div class="panel-heading">
                 <button type="button" class="close" aria-label="Close"><span aria-hidden="true">×</span></button>