ci: ci-builder fix

Give the correct path to the dockerfile

.changeset/heavy-shoes-know.md

+---
+'@eth-optimism/ci-builder': patch
+---
+
+Retrigger release of ci-builder

.github/workflows/release.yml

@@ -233,7 +233,7 @@ jobs:
         uses: docker/build-push-action@v2
         with:
           context: ./ops/docker/ci-builder
-          file: Dockerfile
+          file: ./ops/docker/ci-builder/Dockerfile
           push: true
           tags: ethereumoptimism/ci-builder:${{ needs.release.outputs.ci-builder }},ethereumoptimism/ci-builder:latest