chore: try including platform pair in cache key

Author: brendan-kellam

.github/workflows/ghcr-publish.yml

@@ -73,8 +73,8 @@ jobs:
         with:
           context: .
           labels: ${{ steps.meta.outputs.labels }}
-          cache-from: type=gha
-          cache-to: type=gha,mode=max
+          cache-from: type=gha,scope=${{ env.PLATFORM_PAIR }}
+          cache-to: type=gha,mode=max,scope=${{ env.PLATFORM_PAIR }}
           platforms: ${{ matrix.platform }}
           outputs: type=image,name=${{ env.REGISTRY_IMAGE }},push-by-digest=true,name-canonical=true,push=true,annotation.org.opencontainers.image.description=Blazingly fast code search
           build-args: |