Update sigstore/cosign-installer digest to fb28c2b

Author: renovate[bot]

.github/workflows/docker-image.yml

@@ -36,7 +36,7 @@ jobs:
       # https://github.com/sigstore/cosign-installer
       - name: Install cosign
         if: github.event_name != 'pull_request'
-        uses: sigstore/cosign-installer@08bb361e01a71697a353a4d79b633cccf31f5530
+        uses: sigstore/cosign-installer@fb28c2b6339dcd94da6e4cbcbc5e888961f6f8c3
         with:
           cosign-release: 'v2.2.4'