allow skipping sdk version check on deploy (#637)

Author: yoonsio

cmd/lk/agent.go

@@ -129,6 +129,7 @@ var (
 					Flags: []cli.Flag{
 						secretsFlag,
 						secretsFileFlag,
+						skipSDKCheckFlag,
 					},
 					// NOTE: since secrets may contain commas, or indeed any special character we might want to treat as a flag separator,
 					// we disable it entirely here and require multiple --secrets flags to be used.