chore(deps): update sigstore/cosign-installer action to v3.9.1 (#564)

Co-authored-by: renovate[bot] <29139614+renovate[bot]@users.noreply.github.com>

Author: renovate[bot]

.github/workflows/release-publish.yml

@@ -66,7 +66,7 @@ jobs:
           password: ${{ secrets.GITHUB_TOKEN }}
 
       - name: Install sigstore/cosign
-        uses: sigstore/cosign-installer@d7d6bc7722e3daa8354c50bcb52f4837da5e9b6a # v3.8.1
+        uses: sigstore/cosign-installer@398d4b0eeef1380460a10c8013a76f728fb906ac # v3.9.1
 
       - name: Push charts to GHCR
         env:

.github/workflows/tests-cluster-chainsaw.yaml

@@ -34,7 +34,7 @@ jobs:
           fetch-depth: 0
 
       - name: Install Cosign
-        uses: sigstore/cosign-installer@d7d6bc7722e3daa8354c50bcb52f4837da5e9b6a # v3.8.1
+        uses: sigstore/cosign-installer@398d4b0eeef1380460a10c8013a76f728fb906ac # v3.9.1
 
       - name: Setup kind
         uses: ./.github/actions/setup-kind