Update setup_install.yml

roles/matrix-synapse/tasks/synapse/setup_install.yml

@@ -132,7 +132,7 @@
 - set_fact:
     matrix_synapse_media_storage_providers: |
       {{
-        matrix_synapse_media_storage_providers|default([])
+        media_storage_providers|default([])
         +
         [
           {