Update docker/build-push-action action to v7 (#32)

Co-authored-by: renovate[bot] <29139614+renovate[bot]@users.noreply.github.com>

Author: renovate[bot]

.github/workflows/ci.yml

@@ -46,7 +46,7 @@ jobs:
           images: ${{ env.GHCR_IMAGE }}
 
       - name: Build and export to Docker local cache
-        uses: docker/build-push-action@v6
+        uses: docker/build-push-action@v7
         with:
           # Need load and tags so we can test it below
           load: true
@@ -66,7 +66,7 @@ jobs:
       - name: Build and push by digest
         if: github.ref_type == 'tag'
         id: build
-        uses: docker/build-push-action@v6
+        uses: docker/build-push-action@v7
         with:
           labels: ${{ steps.meta.outputs.labels }}
           annotations: ${{ steps.meta.outputs.annotations }}