chore: add missing write permission to push built Docker images (#38)

## What's Changed

Override permission in the `docker` job.

Closes #37.

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Co-authored-by: Jacob Wujciak-Jens <[email protected]>

Author: kou

.github/workflows/test.yaml

@@ -59,6 +59,8 @@ jobs:
     name: Ubuntu Swift 5.10
     runs-on: ubuntu-latest
     timeout-minutes: 10
+    permissions:
+      packages: write
     env:
       DOCKER_VOLUME_PREFIX: .docker/
     steps: