Update cosign to v3.0.6 (#1659)

Signed-off-by: Cosmin Cojocar <cosmin@cojocar.ch>

Author: ccojocar

.github/workflows/release.yml

@@ -24,7 +24,7 @@ jobs:
       - name: Install Cosign
         uses: sigstore/cosign-installer@v4.1.1
         with:
-          cosign-release: "v3.0.5"
+          cosign-release: "v3.0.6"
       - name: Store Cosign private key in a file
         run: 'echo "$COSIGN_KEY" > /tmp/cosign.key'
         shell: bash