Refactor primary color to settings variable (#1775)

src/pretix/base/email.py

@@ -114,7 +114,7 @@ class TemplateBasedMailRenderer(BaseHTMLMailRenderer):
             'site_url': settings.SITE_URL,
             'body': body_md,
             'subject': str(subject),
-            'color': '#8E44B3',
+            'color': settings.PRETIX_PRIMARY_COLOR,
             'rtl': get_language() in settings.LANGUAGES_RTL
         }
         if self.event:

src/pretix/base/services/notifications.py

@@ -91,7 +91,7 @@ def send_notification_mail(notification: Notification, user: User):
     ctx = {
         'site': settings.PRETIX_INSTANCE_NAME,
         'site_url': settings.SITE_URL,
-        'color': '#8E44B3',
+        'color': settings.PRETIX_PRIMARY_COLOR,
         'notification': notification,
         'settings_url': build_absolute_uri(
             'control:user.settings.notifications',

src/pretix/base/settings.py

@@ -1580,7 +1580,7 @@ Your {event} team"""))
         'type': bool
     },
     'primary_color': {
-        'default': '#8E44B3',
+        'default': settings.PRETIX_PRIMARY_COLOR,
         'type': str,
     },
     'theme_color_success': {