fix: never proxy hot-reload websocket requests #4316
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For Bugs and Features; did you add new tests?
Please let me know what kind of test could be appropriate for this change.
Motivation / Use-Case
Both create-react-app and vue-cli-service have introduced workarounds for this, but it seems to me that this is always desirable behaviour for webpack-dev-server.
vuejs/vue-cli@72ba750
facebook/create-react-app#7444