chore(deps): update actions/attest action to v4.2.1

| datasource  | package        | from   | to     |
| ----------- | -------------- | ------ | ------ |
| github-tags | actions/attest | v4.2.0 | v4.2.1 |

Author: renovate[bot]

.github/workflows/build.yml

@@ -61,7 +61,7 @@ jobs:
         run: cosign sign --yes ${{ env.IMAGE }}@${{ steps.publish.outputs.digest }}
 
       - name: Attest the Docker image
-        uses: actions/attest@f7c74d28b9d84cb8768d0b8ca14a4bac6ef463e6 # v4.2.0
+        uses: actions/attest@508db95dd578ae2727ebd6217d5ba78e4fbda05d # v4.2.1
         if: env.DRY_RUN != 'true'
         with:
           subject-name: ${{ env.IMAGE }}