set sigstore action version to proper version

.github/workflows/build.yml

@@ -55,7 +55,7 @@ jobs:
           sudo apt-get update
           sudo apt-get install -y podman
       
-      - uses: sigstore/cosign-installer@sigstore/cosign-installer # v3.9.0
+      - uses: sigstore/cosign-installer@v3.9.0
         with:
           install-dir: /usr/bin
           use-sudo: true