this is an example where is pin the max version

"packageRules": [
    {
      "matchDatasources": [
        "docker"
      ],
    },
    {
      "matchPackageNames": ["**/elasticsearch"],
       "allowedVersions": "<8.0.0"
    }
  ],

you would need to adapt that for gems obivously. but i think you get it 😉