chore: update config sample to make it clear what github address should look like

Signed-off-by: Devin Buhl <devin@buhl.casa>

config.sample.yaml

@@ -123,7 +123,10 @@ bootstrap_bgp:
 # 2. (Required) Flux details - Flux is used to manage the cluster configuration.
 #
 
-# (Required) GitHub repository URL (for private repos use the ssh:// URL)
+# (Required) GitHub repository URL
+#   For a public repo use the 'https://' URL (e.g. "https://github.com/onedr0p/cluster-template.git")
+#   For a private repo use the 'ssh://' URL (e.g. "ssh://git@github.com:onedr0p/cluster-template.git")
+#     If using a private repo make sure to following the instructions with the 'bootstrap_github_private_key' option below.
 bootstrap_github_address: ""
 
 # (Required) GitHub repository branch