fix(plugin-webpack): protocol recognizes webpack's devServer setting

[Dogdriip]

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Summarize your changes:

If you have opened your dev server with https via the devServer.server setting, make it aware of it.

[BlackHole1]

I have a question, if we want to support https, should we support custom certificates (i.e., server.options)?

Ref: https://webpack.js.org/configuration/dev-server/#devserverserver

[Dogdriip]

I have a question, if we want to support https, should we support custom certificates (i.e., server.options)?

Ref: webpack.js.org/configuration/dev-server

As the ref says, if we don't give it a certificate option, it will default to a self-signed certificate. If we use a custom certificate, I don't think there's anything forge needs to support.