Replace spaces with - in prefix too

[datashaman]

Calling prefix() independently of nameWithPrefix() results in a function prefix which has spaces in it, which is not valid for a Lambda function name.

[wilsenhc]

Would be great if you added a new test case(s) for this so it doesn't break again in the future

[yoeriboven]

I had the same problem but it was because of a dot. Could you also filter out '.' besides spaces?

[Francismori7]

I have an issue on my end with ACCENTS, for instance we use "Ratté" in APP_NAME.

Should we just slugify the prefix? Str::slug()

    /**
     * Used by Sidecar to differentiate between apps and environments.
     *
     * @return string
     */
    public function prefix()
    {
        return 'SC-' . Str::of(config('app.name') . '-' . Sidecar::getEnvironment())->slug() . '-';
    }

[aarondfrancis]

I think #30 fixes all of these issues, there were quite a few things I didn't consider w.r.t. the app name, but we should be good to go now. Thanks for the PR and the test cases! Lemme know if you hit anything else.