Merge pull request #7 from tateru/fix-ci

CI: update cosign

.github/workflows/docker-publish.yml

@@ -39,9 +39,9 @@ jobs:
       # https://github.com/sigstore/cosign-installer
       - name: Install cosign
         if: github.event_name != 'pull_request'
-        uses: sigstore/cosign-installer@f3c664df7af409cb4873aa5068053ba9d61a57b6 #v2.6.0
+        uses: sigstore/cosign-installer@v3.3.0
         with:
-          cosign-release: 'v1.11.0'
+          cosign-release: 'v2.2.2'
 
 
       # Workaround: https://github.com/docker/build-push-action/issues/461
@@ -87,8 +87,6 @@ jobs:
       # https://github.com/sigstore/cosign
       - name: Sign the published Docker image
         if: ${{ github.event_name != 'pull_request' }}
-        env:
-          COSIGN_EXPERIMENTAL: "true"
         # This step uses the identity token to provision an ephemeral certificate
         # against the sigstore community Fulcio instance.
         run: echo "${{ steps.meta.outputs.tags }}" | xargs -I {} cosign sign {}@${{ steps.build-and-push.outputs.digest }}