fix(nextcloud): Add https override

This patch should fix nextcloud's own wrong perception of being
available over http instead of https.

apps/base/nextcloud/release.yaml

@@ -56,6 +56,8 @@ data:
             ),
             'forwarded_for_headers' => array('HTTP_X_FORWARDED_FOR'),
           );
+    phpClientHttpsFix:
+      enabled: true
     internalDatabase:
       enabled: false
     externalDatabase: