Print warnings or error out when invalid arguments are passed

[thvasilo]

With the number of arguments that we parse, it's likely that an arg can be misspelled.

e.g. I ran into the case where I was trying to pass --save-embeds-path instead of save-embed-path which led to my job hanging without an obvious reason.

When unknown arguments are passed to the launch scripts, we should be at least print out a warning, or error out the job (as it will likely lead to something the user did not intend).

More context:

What's happened is that the yaml file had a value for the path, which I tried to override through the CLI.

But the misspelled CLI arg was just ignored and it tried to use the one from the yaml.

[classicsong]

Print out a warning.
We need to support customized args.