upstream sync: Sort releases for deterministic workflows

For some reason the most recent source repo sync workflow has created
PRs with upstream sync workflow jobs in a random order. This is not good
as they will keep changing over time. Sort the jobs based on the release
name.

ansible/roles/source-repo-sync/templates/upstream-sync.jinja

@@ -8,7 +8,7 @@ permissions:
   contents: write
   pull-requests: write
 jobs:
-{% for release in repository_manifest.releases %}
+{% for release in repository_manifest.releases | sort %}
   synchronise-{{ release | replace(".", "-") }}:
     name: Synchronise {{release}}
     uses: stackhpc/.github/.github/workflows/upstream-sync.yml@main