Improve webpack-dev-server compatibility with non-localhost setups.

What does this MR do?

Creates a webpack helper method which doesn't automatically prepend the host and port when the dev_server option is enabled. Since we proxy everything through rack middleware this is redundant and makes running the GDK on anything other than localhost difficult.

Are there points in the code the reviewer needs to double check?

This should be pretty straight forward.

Does this MR meet the acceptance criteria?

• Changelog entry added, if necessary
• Documentation created/updated
• Tests
  • All builds are passing
• Conform by the merge request performance guides
• Conform by the style guides
• Branch has no merge conflicts with master (if it does - rebase it please)
• Squashed related commits together

What are the relevant issue numbers?

Closes #27729 (closed)