feat(ansible): add branch reference as variable in gitrepository (#919)

* feat: add branch reference as variable in gitrepository

* Update bootstrap/vars/config.sample.yaml

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Co-authored-by: Devin Buhl <onedr0p@users.noreply.github.com>

bootstrap/templates/kubernetes/flux/config/cluster.yaml.j2

@@ -7,7 +7,7 @@ metadata:
 spec:
   interval: 30m
   ref:
-    branch: main
+    branch: {{ bootstrap_github_repository_branch | default('main', true) }}
   url: "https://github.com/{{ bootstrap_github_username }}/{{ bootstrap_github_repository_name }}.git"
   ignore: |
     # exclude all