chore(deps): update sigstore/cosign-installer action to v4

Author: renovate[bot]

.github/workflows/build-boxkit.yml

@@ -89,7 +89,7 @@ jobs:
 
       # Sign container
       - name: Install cosign
-        uses: sigstore/cosign-installer@d7543c93d881b35a8faa02e8e3605f69b7a1ce62 # v3.10.0
+        uses: sigstore/cosign-installer@cad07c2e89fa2edd6e2d7bab4c1aa38e53f76003 # v4.1.1
 
       - name: Sign container image
         if: github.event_name != 'pull_request'