Update the release notes

Signed-off-by: Leandro Lucarella <luca-frequenz@llucax.com>

Author: llucax

RELEASE_NOTES.md

@@ -4,6 +4,7 @@
 
 This release migrates lightweight GitHub Actions workflow jobs to use the new cost-effective `ubuntu-slim` runner.
 It also updates cookiecutter pyproject license metadata to SPDX expressions to avoid setuptools deprecation warnings.
+The auto-dependabot workflow now uses a GitHub App installation token instead of `GITHUB_TOKEN` to fix merge queue and auto-merge failures.
 
 ## Upgrading
 
@@ -44,3 +45,10 @@ But you might still need to adapt your code:
 
 - Switched `project.license` to SPDX expressions and added `project.license-files`.
   This removes deprecated setuptools license metadata and avoids build warnings.
+
+- Fixed auto-dependabot workflow failing to trigger merge queue CI or complete
+  auto-merge. The workflow now uses a GitHub App installation token (via
+  `actions/create-github-app-token`) instead of `GITHUB_TOKEN`, which was
+  suppressing subsequent workflow runs by design. Workflow permissions have been
+  reduced to the minimum needed for the workflow (`contents: read` and
+  `pull-requests: write`).