don't remove demodata package but replace it with the last compatible one

composer.json

@@ -3,11 +3,11 @@
   "description": "Metapackage to switch the OXID 7 Enterprise Edition default template renderer Twig to Smarty, also changes the backend theme to Smarty. After this installation, install your desired smarty-based theme (like Wave or Flow).",
   "require": {
     "d3/oxid-smarty-renderer-metapackage-pe": "*",
-    "oxid-esales/smarty-component-ee": "*"
+    "oxid-esales/smarty-component-ee": "*",
+    "oxid-esales/oxideshop-demodata-ee":"^7.0"
   },
   "replace": {
-    "oxid-esales/twig-component-ee": "*",
-    "oxid-esales/oxideshop-demodata-ee":"*"
+    "oxid-esales/twig-component-ee": "*"
   },
   "license": "GPL-3.0-or-later"
 }