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/vars/config.sample.yaml

@@ -7,6 +7,8 @@
 bootstrap_github_username:
 # Github repository (e.g. flux-cluster-template)
 bootstrap_github_repository_name:
+# Github repository branch (e.g. main)
+bootstrap_github_repository_branch: main
 # Age Public Key (e.g. age15uzrw396e67z9wdzsxzdk7ka0g2gr3l460e0slaea563zll3hdfqwqxdta)
 bootstrap_age_public_key:
 # Choose your timezone (e.g. America/New_York)