fix: consider custom devServer config

[graphicfox]

I´m using a custom Docker setup and had trouble to get the watch-admin running. After some testing i found a few things.

I had to first add the url to the config and second add the devServer config.

webpack: (config, webpack) => {
config.devServer = {
host: '0.0.0.0',
useLocalIp: false
};
return config;
},

After that strapi develop --watch-admin was accessible over the docker ip. But because the config gets not forwarded in the opts, the hot reload doesn't work.
That's because this doesn't get the args that i setup.

function createDomain(options, server) {
const protocol = options.https ? 'https' : 'http';
const hostname = options.useLocalIp
? ip.v4.sync() || 'localhost'
: options.host || 'localhost';

If there is a another way I would like to know. Otherwise I would appreciate this small hotfix.

Here my original problem -> https://stackoverflow.com/questions/8925820/javascript-object-push-function

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[soupette]

LGTM!

Thank you for your contribution.