Attempt setting SECURE_PROXY_SSL_HEADER on stg PDC.

roles/pdc/frontend/templates/settings_local.py

@@ -103,6 +103,11 @@ REST_API_VERSION = 'v1'
 # https://github.com/product-definition-center/product-definition-center/issues/352
 USE_X_FORWARDED_HOST = True
 
+{% if env == 'staging' %}
+# https://pagure.io/fedora-infrastructure/issue/6122
+SECURE_PROXY_SSL_HEADER = ('HTTP_X_FORWARDED_PROTO', 'https')
+{% endif %}
+
 BROWSABLE_DOCUMENT_MACROS = {
     # need to be rewrite with the real host name when deploy.
     'HOST_NAME': 'http://{{ inventory_hostname }}:80',