Chore: Remove provisional APIVersion from plugin info (#89831)

docs/sources/developers/plugins/plugin.schema.json

@@ -582,11 +582,6 @@
         },
         "required": ["extensionPointId", "title", "type"]
       }
-    },
-    "apiVersion": {
-      "type": "string",
-      "description": "[internal only] The API version for the plugin. Used for Datasource API servers. This metadata is temporary and will be removed in the future.",
-      "pattern": "^v([\\d]+)(?:(alpha|beta)([\\d]+))?$"
     }
   }
 }