Add throwing error when specifying unsupported os in Vagrant (#9965)

Vagrantfile

@@ -83,6 +83,13 @@ $playbook ||= "cluster.yml"
 
 host_vars = {}
 
+# throw error if os is not supported
+if ! SUPPORTED_OS.key?($os)
+  puts "Unsupported OS: #{$os}"
+  puts "Supported OS are: #{SUPPORTED_OS.keys.join(', ')}"
+  exit 1
+end
+
 $box = SUPPORTED_OS[$os][:box]
 # if $inventory is not set, try to use example
 $inventory = "inventory/sample" if ! $inventory