ci: grant contents write permission so SBOMs can be attached to releases

Co-authored-by: bakerboy448 <55419169+bakerboy448@users.noreply.github.com>

Author: Copilot

.github/workflows/docker-build.yml

@@ -30,7 +30,7 @@ jobs:
   build:
     runs-on: ubuntu-latest
     permissions:
-      contents: read
+      contents: write
       packages: write
       id-token: write
     outputs: