Fix accidental revert of "Proxy webpack dev server in test environment""

What does this MR do and why?

It looks like !83512 (merged) has accidentally reverted (see relevant issue and relevant merge commit):

This MR resurrects the changes from !83337 (merged).

Screenshots or screen recordings

Here's a recording of us verifying that these changes fix local webpack issues on a recent master

How to set up and validate locally

Copied from this old MR

I wasn't able to reproduce #352649 (closed) even after I downgraded rack-proxy to v0.6.0.

With this branch, this should pass:

bundle exec rspec --fail-fast spec/features/groups_spec.rb spec/features/projects/new_project_spec.rb spec/features/merge_request/user_sees_pipelines_spec.rb ee/spec/features/issues/user_uses_quick_actions_spec.rb

Relates to #352649 (closed)

Edited by Paul Slaughter

Merge request reports

Loading