chore: drop secrets: inherit from stale workflow

The shared standards-stale workflow only uses actions/stale@v9 which
runs on GITHUB_TOKEN — no custom secrets are declared. Removing
secrets: inherit follows least-privilege principle.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

Author: roshan-gorasia-cko

.github/workflows/standards-stale.yaml

@@ -13,4 +13,3 @@ jobs:
   stale:
     name: Stale
     uses: processout/actions/.github/workflows/standards-stale.yaml@v1
-    secrets: inherit