fix(serve): handle serve args as an array

[knagaitsev]

What kind of change does this PR introduce?
fix

Did you add tests for your changes?
Yes

If relevant, did you update the documentation?

Summary

I changed the args parameter to ...args, because I realized I overlooked this earlier. The problem is that spread syntax is used to pass the CLI args to the function, so I was only passing the first of these strings along to the argument parser. I added a test that involves more CLI flags to check this is fixed.

I'm not sure why serve tests and command were temporarily removed, was there a particular reason?

Also, I don't think adding this line was needed:

process.argv = process.argv.filter(arg => arg !== 'serve');

Does this PR introduce a breaking change?
No

Other information

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