fix(mc-scripts): regression when updating webpack-dev-server to 4.0.0-beta.3

[emmenko]

Caused by #2199

This slipped through in the latest dependency upgrade

causing local dev to not start:

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Latest commit: 02ed088

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@commercetools-frontend/mc-scripts	Patch

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[tdeekens]

Wow. Sneaky.

[tdeekens]

Interesting use case for a E2E test. Instead of building and serving just using the webpack-dev-server maybe 🤔.

[emmenko]

Yeah I was thinking the same, although I would say testing the production bundle is more important.

Maybe we can have a step to only start the dev server? This should then prevent such regressions. We can use the "wait for" to terminate the step once localhost is available.

[tdeekens]

Yes, that's what I thought too. Wasn't meaning to imply that we should replace the production bundle testing with it.