Update docker-publish.yml

Author: TobiasS1402

.github/workflows/docker-publish.yml

@@ -85,7 +85,7 @@ jobs:
       - name: Sign the published Docker image
         if: ${{ github.event_name != 'pull_request' }}
         env:
-          COSIGN_EXPERIMENTAL: "true"
+          COSIGN_EXPERIMENTAL: "false"
         # This step uses the identity token to provision an ephemeral certificate
         # against the sigstore community Fulcio instance.
         run: echo "${{ steps.meta.outputs.tags }}" | xargs -I {} cosign sign {}@${{ steps.build-and-push.outputs.digest }}