fix(ci): use default GITHUB_TOKEN for release-please

RELEASE_TOKEN secret is not configured in this repo and not needed
since release-please only creates PRs and releases.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

Author: mortik

.github/workflows/release-please.yml

@@ -18,4 +18,4 @@ jobs:
       - uses: googleapis/release-please-action@v4
         id: release
         with:
-          token: ${{ secrets.RELEASE_TOKEN }}
+          token: ${{ secrets.GITHUB_TOKEN }}