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/tasks/validation/vars.yaml

@@ -16,6 +16,7 @@
     - bootstrap_cluster_cidr
     - bootstrap_flux_github_webhook_token
     - bootstrap_github_repository_name
+    - bootstrap_github_repository_branch
     - bootstrap_github_username
     - bootstrap_external_ingress_addr
     - bootstrap_internal_ingress_addr