chore: exclude publishing unicorn flavor arm64 package (#223)

## Description

exclude publishing unicorn flavor arm64 package until arm64 is available

## Related Issue

Fixes #
<!-- or -->
Relates to #

## Type of change

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

## Checklist before merging

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

.github/workflows/release.yaml

@@ -41,6 +41,8 @@ jobs:
         exclude:
           - flavor: registry1
             architecture: arm64
+          - flavor: unicorn
+            architecture: arm64
     uses: defenseunicorns/uds-common/.github/workflows/callable-publish.yaml@c52077c870a576d01f169f96d74d1b393c6488ba # v1.1.2
     with:
       flavor: ${{ matrix.flavor }}