chore: hotfix renovate config registries (#45)

## Description

This fixes the registry urls in the package definition.

## Related Issue

Fixes #N/A

## Type of change

- [ ] Bug fix (non-breaking change which fixes an issue)
- [ ] New feature (non-breaking change which adds functionality)
- [x] Other (security config, docs update, etc)

## Checklist before merging

- [x] Test, docs, adr added or updated as needed
- [x] [Contributor Guide
Steps](https://github.com/defenseunicorns/uds-package-mattermost/blob/main/CONTRIBUTING.md#developer-workflow)
followed

renovate.json

@@ -21,7 +21,6 @@
       "groupName": "Mattermost Package Dependencies",
       "labels": ["package-deps"],
       "commitMessageTopic": "package-deps",
-      "registryUrls": ["https://registry1.dso.mil"],
       "matchDatasources": ["docker", "helm", "git-tags"]
     },
     {