Try to speed up ghcr publish using arch matrix

.github/workflows/ghcr-publish.yml

@@ -30,6 +30,9 @@ jobs:
       # This is used to complete the identity challenge
       # with sigstore/fulcio when running outside of PRs.
       id-token: write
+    strategy:
+      matrix:
+        architecture: [amd64, arm64]
 
     steps:
       - name: Checkout repository
@@ -77,7 +80,7 @@ jobs:
           labels: ${{ steps.meta.outputs.labels }}
           cache-from: type=gha
           cache-to: type=gha,mode=max
-          platforms: linux/amd64,linux/arm64
+          platforms: linux/${{ matrix.architecture }}
       
       # Sign the resulting Docker image digest except on PRs.
       # This will only write to the public Rekor transparency log when the Docker