fix: make vlt 6 work

Author: jnptk

backend/mx.ini

@@ -8,6 +8,7 @@ main-package = -e .[test]
 ; example how to override a package version
 version-overrides =
     pytest-plone>=1.0.0a1
+    plone.restapi>=9.14.0
 
 ; example section to use packages from git
 ; [example.contenttype]

frontend/mrs.developer.json

@@ -4,7 +4,7 @@
     "package": "@plone/volto",
     "url": "git@github.com:plone/volto.git",
     "https": "https://github.com/plone/volto.git",
-    "tag": "19.0.0-alpha.0",
+    "tag": "18.20.0",
     "filterBlobs": true
   }
 }